I ordered my JBL from ereader.com and it came with a card that included a listing
of the following sites:
"...available for purchase on
http://www.ereader.com/
(All titles)
http://www.fictionwise.com/
(Secure eReader and multiformat - choose non-encrypted eReader(PDB), ePub, or
Mobi(PRC))"
"Free eBook downloads available from:
http://www.feedbooks.com/
(ePub and Mobi fromat)
http://www.manybooks.net/
(PRC,epub,Mobi and RTF format)
http://gutenberg.org
(ePub format)"
IMHO, the ePub format displays best on the the JBL, with the least effort.
Luck;
Ken