Your RAM IS showing the correct MHz. You are the victim of marketing. The default MHz is 1066. The RAM is capable of running, overclocked, at 1333. I am not looking at the specs, but I will wager that 1333 is not in your RAM's SPD.
Your local computer shop, even if they are willing to OC your system for you, will charge you more money than it is worth, IMO. As a shop owner, I would not OC your system - I would not accept the liability.
If you are still in the first 30 days, I would demand a swap out on the RAM for RAM that includes 1333 in the SPD - RAM that defaults to 1333. This depends, of course, on whether or not the company that sold you the system claimed the RAM would run out of the box at 1333.