You can create an account with coinbase.com and sell/buy bitcoins. The company is U.S. based and is trusted, check it out.
indeed, I just did my first purchase in Coinbase. I'm still waiting for them to deposit the bitcoins (it takes like a week when you are using a bank account), but so far everything looks fine.
Also you can try LocalBitcoins, you can even find people nearby in case you are more interested in a personal interaction. You can use cash, cash deposited on a bank account, WU, Moneygram, etc., they also have a reputation system so you can know who are you dealing with (obviously no reputation system is 100% secure, but it is way better than other sites).
You can also try bitrated.com.
I hope this helps.