Drif Field, the author of a richly sarcastic guide to second-hand and rare bookshops in England, once suggested that the bookshop equivalent of the happy hour was the surly hour - except it lasted all day. Now, thanks to the internet, dealers in these books are witnessing a welcome upsurge in the prices they can charge for many items. And they have not even had to go to charm school.

The market for rare books has always had a bit of a fuddy-duddy, senior common room feel to it. It was, more often than not, a club of gentlemen who, as Mr Field often pointed out, did not seem as if they needed to make money from the enterprise. The internet has transformed that image, having made the trade accessible to a far wider range of customers. And while the internet has been credited with driving prices of many goods downward as a result of competition, in the trade of some rare, collectable second-hand books it has had the opposite effect.

For these items, the market "has been stirred up", says John Critchley, the director of the UK-based Antiquarian Booksellers' Association. With Harry Potter first editions reaching the staggering price of £15,000 (E23,880), shaken rather than stirred might be a more apt description.

Five years ago, if you wanted, say, a nice edition of a Graham Greene novel, you would walk into a rare-book store and ask the staff - if you were prepared to brave their indifference - whether they had anything in stock. Invariably they would look down their nose and say no, while suggesting that you check back in a few months. Sometimes, they took your telephone number and promised to ring if something came up.

But six months down the road, you were often no longer interested. The trade relied on "whim" buying. Even those owners who went to the trouble of producing catalogues - an expensive proposition, costing upwards of £8 (E12.7) per copy to send out - rarely reached an audience wider than their existing client base. However, Paul Minet, a 63-year-old bookseller with nearly 50 years in the trade, says the internet has gone some way towards rescuing his small country bookshop, having given him the passing trade he was lacking.

Competition

Indeed by taking the legwork out of the second-hand and rare-book trade, the internet has introduced more competition between buyers, rather than sellers. Jane Whewell, a UK Department of Trade and Industry employee, made a study of the second-hand book trade and found that 68 per cent of booksellers who have set up their own websites or who have listed with one of the specialist search engines, such as abe.com, have found that their profits have increased.

It is no surprise that Ms Whewell also found that trading on the internet by Provincial Book Fairs Association members is five times higher than the UK industry average.Prices have also been fuelled by the popularity of online auctions such as eBay. A nice copy of a John Le Carre, which used to go for £4,000 or £5,000 (E6,368 or E7,960), will now sell for between £7,000 and £8,000 (E11,114 and E12,736).

Even books that had been considered undesirable (and thus undervalued) a few years ago are finding a new market on the internet. Pom Harrington, of London-based book dealers Peter Harrington Books, credits eBay with creating a demand for books by J.R. Tolkien, author of The Lord of the Rings. A few years ago, Tolkien reprints would cost £10 or £20 (E16 or E32); now they are fetching £300 or £400 (E478 or E637). First editions, previously £3,000 to £5,000 (E4,776 to E7,960), are now priced between £10,000 and £15,000 (Û15,920 and Û23,880).

"There is no question that eBay set the price," Mr Harrington says. In the case of Tolkien, an author much sought after by those who love computers (otherwise known as computer geeks), the net was the ideal rare bookshop. In other words, it was mainly web surfers' interest that turned Tolkien into a collectable author. Ms Whewell also found that the internet has changed booksellers' views of rare or desirable books. Books dealers thought were rare turned out, with the transparency of the internet, to be quite common. On the other hand, books which were not particularly collectable have seen their prices double and continue to climb as a result of online demand.

Mr Minet also credits the web for moving obscure books that may have sat on the shelf previously - "You can sell a military history standing on your head on the internet." (Obscurity may have its limits, however. Researching this article I found a book dealer on the web who specialised in Indian politics, economy and irrigation.)

Collector culture

The popularity of collecting has also soared. Books are becoming harder to get your hands on, even for dealers like Mr Harrington. Four or five years ago, he would bring back a decent haul of books from his road trips around the US; now he finds the only books worth buying have either not yet been put on the internet, or have yet to be catalogued.

For many booksellers, the internet has also opened entire markets that were previously closed. University libraries, once cornered by a few select dealers, are now open to an unlimited number. Peter Harrington Books sold one-third of its catalogue for the San Francisco book fair last year to an American university, before the catalogue had even been printed, by putting it on the internet. Markets such as Japan and Singapore, which were very difficult for continental European and UK dealers, are also opening up.

But prices are not rising uniformly. Mr Minet argues that there is a levelling out of prices, particularly in second-hand books that are out of print. The transparency of the internet has put pressure on dealers to bring their prices more into line. As Drif Field might point out, there was no set cost for a second-hand book - just an average price with often huge variations from bookstore to bookstore.

Mr Minet checks abe.com before pricing his own stock to see what the competition is doing. If there are 50 copies of a book on abe.com, he does not bother to catalogue it at all, but will add it to the shop shelf. If there are 10, and two are British, he aims to price just below the British price. "But, of course, someone will come in below us," he adds. With online book retailers now set to enter the market, the push downward may continue, so the good times for the trade may not last.

Whatever the future market trends, the arrival of the internet is probably bad news for Mr Field. His two main preoccupations - writing his guidebook and operating as an arbitrage dealer in the book trade (spotting bargain first editions in one shop and legging them to another willing to pay him a higher price) - are no longer as viable.

Email Edi Smockum at esmockum@netscape.net