You are very perceptive, ligrill: that's usually the part of the recipe that gets left out! The most important part. ;-) In fairness, though, that's the part that is the hardest to predict. It's affected by a zillion variables, most notably the thickness of the meat and the heat of the fire.
I would suggest setting up a two-zone fire-- hot coals on one half of the grill, and none on the other side. This allows you to cook the food directly over the heat (so, similar to broiling or frying) and/or indirectly away from the heat (so, similar to baking or roasting in an oven). It's also nice to have a kind of 'rescue zone' if you get flareups or whatnot.
Once you've got your fire going, I'd say there are two schools of thought.
1. Sear the meat, then roast it away from the heat.
2. Do what's called a 'reverse sear', where you roast the meat first, then when it's almost finished you sear/mark it on the hot side of the grill.
For your first time, I'd recommend searing first: I'd start with a mostly full chimney of coals, dump it out, and let the grate get hot for a minute or two. Then put the chops right over the hot side for maybe 2 minutes (if your chops are nice and thick), then turn the piece 90 degrees to get some nice sear marks for another minute or so. Go maybe half that time for thinner cuts. Then flip them, repeating the procedure. When the second side is seared, move them off of the direct heat to the cooler side of the grill. With your lid down, you'll prolly have the equivalent of a 400 degree convection oven, so don't leave them on too long. When they feel like they are firming up, check their temp with a meat thermometer inserted in the edge of the meat to the center mass of the chop (just pick up the meat with your tongs to aid in this maneuver). You're looking for 140 internal for a finished temp (the new USDA standard that has been standard in the restaurant industry for years). Make sure you rest your chops for 5 minutes or so before serving (this is really important).
If you're really nervous about this, hedge your bet. Practice on one chop, rest it, and give it a taste. Then cook one or more, and so you go. If your fire gets cool, add some more (lit) coals, but you should be good to cook for at least 30 minutes I would think.