Yay! I'm so glad it was helpful for you. I was especially frustrated with B&N's interface, which only allows you to see their chosen free books, when they have so many to offer (almost 2 million!). They might be selling more Nooks if they let people know that.
Meantime, I'm working on making the searches even more specific for each site, but that's taking some real bona fide programming skill. I'll let you all know when I've updated the links accordingly.
Here's the link again, for anyone who wants to search for freebies: Find Free eBooks!