The University of Chicago Press has a free ebook every month. This month it's their new publication, the first book of the 12 book "A Dance to the Music of Time" epic.
http://www.press.uchicago.edu/ebooks/free_ebook.html
You need to give them your email address, and they email you a link to the page where you can download the .acsm file for the ePub.
It seems to have no geographical restrictions.