For those who don't know, the address is http://www.thedroidlibrary.com
Well, despite being sceptical at first, I signed up, and I am pretty impressed with the site. They have a massive range of eBooks for all Android devices. I've just downloaded the entire Harry Potter series to my Galaxy Tab, plus a few comics.
Overall, I'd recommend it. Theres no harm in trying it out since they have a 60 day money back guarantee.