RBBB Arduino fried?

I bought some RBBB's (Really Bare Bones Board) http://shop.moderndevice.com/products/rbbb-kit from Modern Device and I think I shorted out a pin. It was a noob mistake and I had it hooked up wrong and pressed a button on my breadboard and the power light on it went off and then when I let off the swicht the power light came back on. The ATMega328 chip is fine, I tested it by putting it in another Arduino. Is there a component on the board that I can replace to bring it back from the dead?

The voltage regulator, or the diode. What else is there?

I'm a beginner when it comes to testing these components but I'm assuming that I need to power it up and measure the voltage across the diode and make sure it only flows in one direction and then measure the voltage across the regulator to make sure it's doing its job.

That'd be a good start. Pull the uC, put a 100 ohm resistor load across its power/ground pins so the diode/regulator have to supply 50mA, so if they working.
Resistor will be dissipating 50mA * 50mA * 100 ohm = 250mW, use two 200 ohm in parallel if all you have is 1/4W resistors. The actual current is not critical.