It's not very hard to find a ice fishing auger that suits your needs.  First, you might want to decide whether you want a gas powered auger or a regular hand powered auger.  If you're a senior fisherman, a gas powered auger is more suited for you.  Hand augers take some strength to cut through the ice, especially if it's really thick.

If you're a young or middle aged fisherman, a hand auger is a good choice.  Just remember, it's going to take some strength to cut through the ice.  Just make sure your blades are always sharp, that really helps.

For both gas powered and hand augers, I would not go anything less than eight inches.  There are a lot of brands out there nowadays, just make sure you pick an established company.  Here's a few off the top of my head: Eskimo, Jiffy and Strikemaster.