Michael Selzer, president of Bibliofind (http://www.bibliofind.com), an online database of old, used, rare and new books, likes to think big: "Soon there will be two or three sites on the Web where a reader can find and buy any book in the world." He expects Bibliofind to be one of them. Launched last September, Bibliofind allows booksellers, book lovers, antiquarian dealers -- basically anyone with a book to sell-to list their titles and prices, for a fee ($20 a month), in Selzer's sophisticated database. Visitors (nearly 24,000 a day) can search for free (the book's owner handles shipping to the buyer) in what Selzer said is a five-million-title database of backlist titles from around the world. Selzer said the site is profitable, all revenues are from the monthly fees and membership is about 1000 and growing. Even Amazon.com uses the site for its out-of-print-title searches, Selzer said. Bibliofind has also announced an agreement with Internet Liquidators (http://www.internetliquidators.com), an online auction house, for Internet Liquidators to become exclusive agents for Bibliofind's rare-book auctions on America Online.