New to me!
I buy scifi ebooks at WebScription.net. If they have the book you want; it is always cheaper than Amazon. I then use Stanza on my iPodTouch for reading.
Stanza has not, however, come out for iPad yet and things could look much better.
I just found out that you can open iTunes, then go to ‘File’ > ‘Add File to Library’ and select an ePub format book from your hard-drive. This book will then show up on iBooks as a legit book on your shelf, thumbnail and all! Awesome!
Next up, The Windup Girl by Paolo Bacigalupi (for 6 bucks at Webscription I may add). Yay!