How do you advertise an e-book?

What's the genre? There are a number of genre-specific sites that have forums/loops where you can chat with other authors and leave the info about your book. Submit your book for reviews, too. to sites that are specific to your genre. You could join www.authorsden.com. There, you can create your own page with info and updates about your book, and a lot of people there are self-published too. You could, of course, take out advertising space in small niche magazines. If you're feeling really ambitious, you could make a book trailer (here's a link that's pretty helpful: http://www.associatedcontent.com/article/154495/creating_multimedia_slideshows_and.html) and advertise it for free on www.previewthebook.com. Hope some of those ideas help. Again, without knowing the genre it's hard to give any more specific suggestions.

Amazon sells ebooks. Fictionwise is probably the largest distributor specifically for ebooks, but there are others.

This is why, even though they may not do a lot of advertising, per se, being published by an ebook producer is definetly advantageous.

The best thing to do would probably be to try to get your title sold through individual ebook stores, although bigger sites like fictionwise usually require several titles before distribution.

Also check out Readers Eden.

The problem is, most of these distributors still take %50, which is essentially what an only slightly-better-than-average publishing contract will cost you.

Good luck.