By Bruce McKinney

The term book search engine would seem to be a generic term. To a layman this is a piece of software that searches your expressed criteria in the more than 25 book listing sites on the web, aggregates the results and reports them to you in a reasonable time and in a comprehensible order. In a perfect world this is true. Welcome to the real world. It isn’t quite that easy. Have you ever wondered why a search engine does what it does without asking for even a penny from you? The three search engines we are looking at in this article: Bookfinder, AddAll and UsedBookSearch are free to use and at the same time make a living by directing would-be buyers to listing sites that pay commissions. These commissions are quite small so the process needs to be fully automated. The buyer searches. The search engine locates specific titles on the various sites they search and links would-be buyers to them. For this they get a few pennies. It’s a tough business.

Each of these search engines has a specific group of sites they search. No, they don’t search exactly the same sites though there are five listings sites they all search (in green). The listing sites that each search engine searches are listed in columns (see page two).

Bookfinder lists the most used-book sites as “partners”: 40. UsedBookSearch of the UK lists 13 sites they search and AddAll lists 16 they search. Bookfinder mentions that it searches 50 million titles, UsedBookSearch 45 million, and AddAll simply describes their coverage as 40 bookstores, 20,000 book dealers and millions of books. They are all substantial but they are not the same. How they differ is important to understand and let’s start with this. For the three titles we searched the total number of matches found by UsedBookSearch was 1,002, Bookfinder 89, and AddAll 335.

In searching the complex inventories of the listing sites each search engine takes a unique approach. UsedBookSearch makes a serious effort to show you every match available on the sites they search. It can be slow but if you wait you’ll see a great deal of material. AddAll seems to be running against a clock. Their searches are quite fast but they accomplish this by limiting some of the matches if the total material they locate is substantial. For uncommon books this is rarely the case. Bookfinder creates files of matches rather than a single list, obscuring the fact that they aren’t providing as many matches as the other search engines.