My friend and I were recruited to deal with a similar problem a couple of months ago.
Things we learned (that the internet won't tell you):
1) A skunk 18" long, standing 7-8" high, and 8 or so inches wide will fit through a hole 2x3". Plan accordingly.
2) Skunks are impervious to 95% of air rifles/ pistols available at Wal-Mart.
3) Skunks are silent, and move silently too. Don't even try listening for them. They will approach close to you, intentionally or not. They can charge you.
4) Skunk-stink: insoluble with water or water-based anythings (including tomato juice). Lighter fluid, gasoline, or denatured alcohol might work, but this remains untested. Skunk-stink smells like new tires and garlic up close.
5) Skunks will eat anything you or your pets eat. Smellier bait attracts better, of course, but a trap will just as likely catch possums or local cats. For some reason, egg and tuna salad works best.
6) Skunks are primarily nocturnal. Lights and/ or noise will scare them back into their hiding place, not away from it. Plan accordingly.
7) Skunks are far smarter than the average pest. About the level of an intelligent cat. Thus, trying to drive them out from behind garbage cans by throwing baseballs, the baseball bat, and angle-iron does not work.
8) Skunks can't climb very well. They are, however, adept diggers. Plan entrance-sealing accordingly.
9) Being mammals, skunks might have a weakness with mace/ OC. This remains untested.
10) Have someone help with everything from flanking to driving to hours-long conversations whispered while waiting for the skunk to show up.