A few kegerator related tips I've picked up on:
Don't skimp on regulators, you'll likely be replacing them at some point if you do. I love the micromatic regulators, the big chrome ones with the knurled adjustment knob. Very solid.
I recommend using 3/16" beer line and 1/4" barbs for everything. You'll eliminate most gas leaks before they happen, and whatever line you have left over will be universally useful for whatever you might need to do. It's a little bit of a pain to assemble initially, but trust me, it's more of a pain to lose full tanks of gas repeatedly. NB: you'll probably have to swap out the barb that comes with your regulator for a 1/4" one, so be sure to put that on your list.
Once you get everything assembled, test for leaks by putting 30+ psi on the system without kegs connected, close the tank valve and let it sit overnight. If you still have full pressure, you should be good to go, as long as your keg lids are seated properly.
Make the serving lines longer than you need and you can shorten them later if you really want to.
Welcome to the wonderful world of kegging!