The first thing you should do is check the Blowout Deals. When you have as many books as Amazon has sometimes you just gotta get rid of some of them. And to do this you deeply discount the prices - and I mean deeply discount them. This link takes you directly to the Blowout Book Deal section for Science Fiction and Fantasy Books Blowout Book Deals

If you just feel like browsing

Go Directly to the Fantasy Book Section of Amazon books. This is the official Fantasy Book Section of Amazon.com. From here you can pick from the top sellers or further break it down into categories. If you want to drill down even more specific here are the sub categories you can go directly to:

Alternate History
Anthologies
Arthurian
Contemporary
Epic
General
Historical
History & Criticism
Magic & Wizards
Series

Looking for the best sellers?

A lot of people don't realize that Amazon keeps a best seller list in all the various sub-genres. The great thing about this list is that it is very fresh (updated hourly) So to see what the current Fantasy best sellers are Top Sellers in Fantasy (updated hourly)

Dont underestimate the power of your fellow readers!

One of the best things (actually two things) about Amazon is the user generated guides and user generated listmania lists. These are a great way to see what other people are passionate about in particular niches. For example, if you like a particular author you can find a list that someone has compiled of his/her work or similar work.

 

Amazon Guides:

Amazon Listmania: