how to promote ebook site

I wonder what's the most efficient way to get traffic for an ebook site?

i have been trying reddit, but got spam complaints..

thanks in advance for help.

White Hat:
Comment on PR3 - PR10 Nofolow Blogs that are highly trafficked relating to your niche.
Comment on PR>0 Blogs and new stories that let you leave your website's url in the comment. (Generally anchor text to your name with the url.)

Grey/Blackhat:
Linkwheel low-comepetition keywords (slowly)