There are many different styles of cases you can get for your Kindle; however what you end up purchasing will depend on your particular needs. Do you want one that will stand the Kindle up so that you don't have to hold it when sitting at a table? Do you want one that covers the front as well, closely resembling a book, or do you just want it to cover the back? After you decide what style you are looking for, you may be interested in further exploring some of the following brands and styles, as they are some of the leading Kindle cases on the market.
Amazon makes a lighted leather cover that is extremely popular. It has a small built in light that enables the reader to enjoy their books no matter where they are, being that the Kindle doesn't have a backlight. It comes in an array of different colors and can be purchased directly from Amazon.com. It is one of their top sellers and, being that it is leather, sells for a reasonable price of $59.99.
Duragadeta also makes a case that is rather popular, however this one has a built in adjustable stand and front cover. Normally, it sells for $49.99 if you purchase it directly from the company or other venders but Amazon.com sells it for 18.99. It can be purchased in red, pink, white, or black.
For Kindle users who don't want an actual case but just a protective sleeve to place their Kindle in, Timbuk2 makes an extremely durable sleeve. However, many users suggest that you still purchase a clear protective screen cover so that you can prevent your Kindle from being scratched as you take it in and out of the sleeve. Sleeves are generally much cheaper than full covers. Timbuk2 sells theirs for just $29.99.