Digital Editions and the public library
Well I finally had a chance to go to my county's public library website (Broward, FL) and I saw that they offer Adobe PDF and Mobipocket ebooks for checkout and download to portable devices.
Their PDF books use Adobe Digital Editions and I was pleasantly surprised how easy it was to get books on my 505. Aside from the poor selection (only 327 books in PDF format), the process was painless.
I added a book to my Cart, then checked out. The download launched ADE which authorized the book, then I hooked up the Reader and dragged it over to the PRS-505 bookshelf. Done.
Of course the format is a little funky, it being a re-flowed PDF and all, but it's not half bad.
One thing that confused me was that some books could not be checked out. They were marked unavailable, and had to be put on hold. How dumb is that? They're supposed to be eBooks, right?
Still, Kudos to my library for trying something cool.