The way I chose is I looked at what rooms CC has the freerolls in. From that list I had to consider which of those are US friendly. It became a tossup as a I had HM and some sites ban the use of it and I really dont like anonymous playing (imagine a live room and a curtain around the table and all you see are hands sticking through the curtain).
Hello. I recommend that you create an account on 888. This site has a great promotional system for new players, you can regularly get good tickets to freerolls or any other bonuses. The only drawback is the work of their support service. Sometimes they answer questions within 10 days.