Their alphabetical listings are easy to search by publisher, grade level or subject and the listings are generally up-to-date.
I am selling off some Bob Jones 2nd Grade curriculum so take a look at my "page" as an example.
The site may seem low-tech but I find it much easier to use than eBay. Also, check out their Bible reading plan record sheets. I found the sheets to be useful in recording the way I naturally tend to read my Bible.
Lots of interesting items on the Homeschool Classified site so check it out.