If stock-market tremors threaten a wobble in the contemporary-art market, the business class of the London art world won’t let it show. This autumn has more moving and shaking than ever before planned for the artfair season, suggesting dealers and gallerists believe the boom in sales, which smashed auction-house records on both sides of the Atlantic in June, can not only be sustained but expanded. That sub-prime mortgage stuff is evidently meaningless to Russian billionaires and Hollywood royalty, then.

Whether a correction is imminent or not, the prices of most famous artists are still way beyond ordinary mortals. London’s appeal for mega-rich collectors is mainly down to Frieze, an elite-level visual Glaston-bury, where the rest of us can press our noses to the vitrines and, if nothing else, buy a subscription to the magazine that spawned it.

“The best art is the most expensive,” Sotheby’s silver-tongued star auctioneer, Tobias Meyer, once declared, “because the market is so smart.” But how do those with smaller pockets gain some of that expertise? The standard advice is, “Buy with your eyes, not your ears”, as purchasing art is among the most subjective decisions you can make, and its value won’t necessarily rise. If you want any kind of significant collection, however, you’d be wise to heed another of Meyer’s bons mots and “Make the market feeling your own”. That doesn’t mean slavishly following fashion – it’s vital to develop your own taste – but understanding what sells, for how much and why. Money is power in art circles, but knowledge is empowerment.

Websites such as Artnet.com and Arts daily.org are excellent for news and prices, the internet being fertile ground for prints, limited editions and student originals, too – if you’ve done your research. Identifying promising graduates is time well spent, as acquiring pieces early in a career can pay dividends later. Joining the Contemporary Art Society, which runs networking groups for beginner, intermediate and advanced collectors, won’t guarantee good fortune, but its studio visits, curator talks and tours of private collections are bound to be instructive.

Okay, so a five-figure overdraft facility would be nice, and it is worth having the charm of George Clooney, but how far does £500, £1,000 and £5,000 go at the leading fairs? And what will those sums buy you in the best online galleries? Let’s do the rounds.

THE OLD GUARD

British Art Fair, Sept 11-16 (www.britishartfair.co.uk); Art London, Oct 4-8 (www.artlondon.net )

Twenty years after beginning in a hotel basement, the 20/21 British Art Fair continues its patriotic duty at the Royal College of Art. Despite the whizz-bang prefix, its strongest suits remain mid-20th-century figures, with prices increasing for Jacob Epstein, Graham Sutherland and David Bomberg. More affordable from that era is Bernard Menin- sky, whose drawings fetch about £2,000. More recent work includes an Eduardo Paolozzi plaster cast, Clenched Fist, 1995 (£650); John Hoyland’s Spanish Hat, 1996 (£2,500); and David Hosie’s Lovers with Glider, 2007 (£3,200). At the nearby Royal Hospital, Chelsea, Art London, erecting its marquee for the ninth time, is also something of a veteran. Marlborough Fine Art joins this year, with Frank Auerbach, Maggi Hambling and Picasso in its crates. Elsewhere, Steven Marshall’s hologram-like painting, Deleted Scene, is less than £500, and a Leonard Cohen sketch (yes, the song-writer draws as well) is yours for £1,225. Fancy an ancient-looking fish? Pieter Vanden Daele’s piscine bronze, Ignatius, is £5,000. Scandinavian and Inuit art are on the menu, too.

THE LEADER OF THE PACK

Frieze, Oct 11-14 (www.frieze.com )

People who wear sunglasses at night, even in affluent middle age, flock to Frieze. It’s cool in the way that newly minted $1,000 bills are, with enough of a festival atmosphere that regular folk don’t feel spooked. Deals will be wheeled, and the 151 galleries should make a packet – £500 is peanuts here, but it would snap up Spartacus Chetwynd’s requiem mask for Steve Irwin, her Xeroxed tribute to the late crocodile guy. Genuine poignancy comes with a Francesca Woodman photograph (£3,500); she took her own life at 22, but her angelic gloom, an obvious influence on Sam Taylor-Wood, endures. Your best bet, though, is to eavesdrop on whoever is splashing big bucks and copy them.

NEW KIDS ON THE BLOCK

Bridge Art Fair (www.bridgeartfair.com) and Pulse (www.pulse-art.com ), both Oct 11-14

Frieze exerts a huge gravitational pull on stellar collectors, and two US shows intend to use some of that force. The Bridge Art Fair is taking over the Trafalgar Hotel for the purpose, but Pulse, setting up shop in Bloomsbury, looks more exciting. Catering for “mid-career” artists, it draws in galleries from Bologna to Beijing and aims to step between established and alternative fairs. Standout work includes Jim Torok’s intense portrait of the artist Ed Ruscha, Kevin Francis Gray’s haunting resin statue, Voodoo Girl, and Tatsumi Orimoto’s nightmarish Bread Man Son, who resembles the Elephant Man after he mistook a baker for a plastic surgeon. Allison Schulnik’s heavily impasted paintings are on sale for £500, a darkly vivid Adam Thompson photograph is available for £1,000, and Tim Bavington’s stripy optics and Bjorn Schulke’s kinetic, Alexander Calderesque sculptures weigh in at about £5,000.

YOUNG TURKS

The Future Can Wait, Oct 9-14; Zoo, Oct 12-15 (www.zooartfair.com)

Fifty new artists seize the now at the Atlantis gallery with The Future Can Wait (website launching next month), a group show, not a fair. Prices start at £500 for Jennifer Allen’s Happy Christmas, Mom and Dad, a DVD postcard along the lines of “I went to London and became a lap dancer”; Dafur, a compelling portrait by Sam Jackson, costs £1,000; and £5,000 buys admittance to Gordon Cheung’s dystopian landscapes. Now lodging behind the Royal Academy, Zoo, the fair for galleries less than six years old, is maturing in style. Your £500 is best spent here on the print and multiple editions chosen by David Thorp, a respected curator. DVDs of Venu-sia, a film by Aline Bouvy and John Gillis, are £1,000; conceptualism fans can splurge that amount on Susan Collis’s 18ct gold screws, while £5,000 immerses you in the murk of Maryon Park, by Nils Nova. With all work selected by Thorp, the critic Ossian Ward and the Whitechapel gallery director Iwona Blazwick, Zoo has cred in spades.

THE BARGAIN HUNTERS

Affordable Art Fair, Oct 18-21 (www.affordableartfair.com); Salon, Sept 13-Oct 5 (www.salongallery.co.uk); BraveArt, Sept 20-23 (www.braveart.co.uk)

Hoxtonites and Mayfair insiders are horribly sniffy about the Affordable Art Fair, probably because the brand is so successful. Its top price is £3,000, yet last year the combined sales total for its spring and autumn shows was £7.3m. While there is pedestrian work, little gems turn up by, say, Elizabeth Blackadder, Howard Hodgkin and Robert Indiana. The event founder Will Ramsay’s own pitch, Will’s Art Warehouse, is a good place to unearth new names. And it’s not as if every unheralded painter at AAF lacks art-historical nous: take Philip Gurrey’s Velazquez homage, Prince Baltasar Carlos as Hunter (£1,000). Buyers on tight budgets will also visit the Salon gallery for its pick of the postgraduates, including Hannah Knox (from about £500) and Geoffrey Stein (£4,000 on average), and its Scottish equivalent, BraveArt, at the Atlantis.

THE DOT COMMIES

Eyestorm (www.eyestorm.com ); New Blood Art (www.new-blood-art.com); Degreeart.com; Counter Editions (www.countereditions.com); Artshole (www.artshole.co.uk)

Eyestorm, among the first online galleries, has been revamped under new management. Clinical sculptures by Marc Quinn (of Trafalgar Square plinth fame) and pop-art pieces by Richard Trupp (a former Jerwood prize nominee) are £500-£1,500, while Vic Reeves’s avian scrawls, celeb-hunters should note, are less than £300. A neat colour-matching facility at New Blood Art allows you to check how David Wightman’s target paintings (£600-£1,000) or Robert Pereira Hind’s free-fall snapshots (£700) might look on your wall. Works by new and recent graduates, including the comely Kate Marshall and optically intriguing Andy Owen, both for £2,500 or less, are on view at Degreeart.com. Prints and multiples by the likes of Peter Doig, Tracey Emin and Gillian Wearing are great value at Counter Editions, from £500. Last, keep your finger on the pulse of the emerging scene at Artshole, which claims 500,000 hits a month. Artists upload their portfolios, and you can buy from them direct (often for less than £100) as well as monitoring exhibition and other art news.

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