Yep, a good destination. Access to the Gutenberg Project is built into Stanza.

baen.com offers a library of free science fiction and fantasy titles. I make a point of showing my appreciation by buying from them when they have a book I want. Besides, their prices are good and they often have the title before anyone else. Only to be expected when they are the publisher.

Just go to their website and download to your heart's content.

If you are going to use the Stanza app anyway, you might as well use it to access the library. It saves a few extra steps.

Of course it will only offer you the ePub versions that way, and there may be a few books no in that format. If you are all-out searching for a public domain book and don't care what format or device you need to read it, going directly to the site is the best bet.

I've done it both ways, depending on my needs of the moment.