So you have some Bitcoin and you want to cash it out eh? Well first find yourself an ATM that accepts sell orders and get that wallet ready (in more ways then one!). Just like any other ATM the fee that you are charged and what price you sell (or buy at) is determined by the owner of the ATM. These fees can range from 4-10% and don't expect to get the best price. The owner sets the prices and it can get private dance room expensive to buy or sell, so make sure you weight those options.
If you live in a major metro area in the United States chances are you have a Bitcoin ATM within modest driving distance. I live in Long Beach, California and there are quite a few in my city and even more as you travel north to Los Angeles.
CoinATMRadar.com is a great resource for finding a local Bitcoin ATM. They have a large listing and it's easy to navigate. They also have some helpful articles. The info they give on each location is nice, although it may be outdated.