There is also a searchable database of job postings and a page of newly added highlights. PostgreSQL is a free database system, maintained by a group similar to the Linux community. I wrote the Perl CGI programs that process forms on the site when you ask to be added to a mailing list or sign up to attend their annual conference. I did the database programming for the Digital Bibliophile Community . This site has a very large MySQL database of used books from various different used book stores.
Book dealers can upload files of book listings in any of several formats.
The programs are written in Perl, using a MySQL database. And, of course, I designed the pages you are looking at now.