noob. Cornelius Keg + Kegerator... how do I connect the two?

Noob here! So, I just got an awesome free kegerator and I want to be able to dispense beer from a corny keg through the kegerator faucet. There is a beer line already connected to the faucet and I have a CO2 tank, but I haven't the slightest idea how to connect the two. Help!

More specifically, I'm unsure what items I will need to purchase to make the conversion happen? Are there any threads or links someone can send my way? Schematics help a ton.

There are two types of Corny's; ball lock and pin lock. The pin locks are pretty easy to identify by the two small pins on the connectors:
You will need to go to buy one gas, and one beer connector appropriate for the type of corny you have. You will need to replace the existing connectors on the kegerator with the connectors you just purchased. When you open the lid on the corny, the gas line will not have the pick up tube connected to it. You will also need a couple of hose clamps to tighten the new fittings to the lines, you may also want to consider buying about 10' of "beer" line so that you can balance the system depending upon the volume of co2 you run, and just for sanitation purposes, if it was a used kegerator.
Pin locks:

Ball locks:

Do you think you will ever want to swap in a commercial keg on occasion? If so you might consider MFL beer and gas connectors instead of hose barbs, the buy MFL swivel hose barbs to terminate your lines. Then add MFL tailpieces to your original sankey connector.

A kit like this would have all the parts, although you might shop around and find it cheaper.