Book Catalog

Just wondering how you can quickly catalog a loftful of books - when we moved house 12 years ago the attic seemed a perfect place to store all those books we wanted to keep. Now, they're still there gathering dust and dead spiders webs. lets see if we can get the book titles into a catalog by just entering the isbn numbers?
so have done a quick search and found out about a website service, some programs for sale, but will they work.
Seems life could be spent in future catalogging where weve been, rather than knowing where we'll go
heres some paths i might explore

http://www.dawsoninteractive.com/articles/article/php-isbn-lookup-tool/