I would try on a lot of shoes to see which one fits best. For road riding I would look at a carbon sole, and I personally like Speedplay Zeros.
If you are looking at mountain bikeing I can't be of much help, as I have no experience there.
Good luck and remember sometimes it's worth it to spend just a little more for better quality. A long time after you forgot how much you paid for something, you still have to live with the product.