Just use Google under 'coin and stamp dealers' in your state or city.
Make sure! you go to one that is not a small operator, and one that has been doing it for some time.
Plus: Google what you have and see the value, on line.
e.g. 1912 Penny what is it worth.(just type in certain items)....
I would recommend going to an antique store and see if they can tell you. Alternatively you can contact an evaluator, but they would most likely charge. There is a website called Value My Stuff (http://www.valuemystuff.com) that will do online evaluations if you send them a picture of your coins.
There are independent antique valuers that can also assist. Otherwise a friend of mine went to the mint (not sure in which city) and they also helped. Ensure you're dealing with someone reputable and licensed.