I'd say I'd rank as "Good". I grew up in a home with an audioholic father who was stereophile devotee. I learned the basics from him, and shift in and out of the hobby as I have time. I just recently got back into home theater, and upgraded to a nice plasma and am searching for some speakers and a new receiver.
I have a reasonable ear and generally don't have setup problems, except with what I consider very poorly designed or buggy hardware. Havin the Internet at your fingertips makes some types of setup easier. I can calibrate things from sight and sound for basic things, but I also just recently got some TV calibration DVDs, and I also just ordered an audio calibration disc, and I recently purchased a SPL meter, so I can do some more scientific testing, and learning. I do similar hookups and also often do buying/recommending for family and friends. I don't really like how complicated system setup has become, but I can live with it because I change my hardware fairly slowly and deliberately. I hate user manuals that are just lists of setup options with no description of what the option choices really mean, and explain in detail why to choose one over other.