1. Go to thehorizon webhost review sites such as webhostin,
2. Next, for each web hosting X, do a "X sucks" search on Google. Read some complaints and see if you may encounter the same problems like them. Some of the complaints may relate to certain groups of users only such as VPS, dedicated server users or resellers. So you may not be affected if you are not from these categories.
3. Eliminate those hostings you feel uncomfortable with, and look for the best bargain hosting for your money.
Some of the best are Justhost, Fatcow and Webfaction. Best really depends on your requirements and needs. It is different from one person to another. If anybody tells you a webhost is the best, they are lying or being very biased.