I agree whole-heartedly, and about pretty much EVERYTHING I own. It's just part of my character that I need to be able to fix and service whatever thing I might have in my life, and so learn enough about it to do so.

But on topic: just recently my FD started making a lot of noise--shifting fine, but the chain seemed to only miss the guide on the middle two rear cogs on both chainrings. BUmmer. Trimming seemed to help sometimes, sure, but also sometimes disappeared. This being a new bike, I took it into the LBS where purchased and had them do a tune-up, letting them know about the FD. It was a little better when I got it back, but still maddening. So I found the Shimano adjustment guide online and read some pages on adjusting FDs...ten minutes later I had it properly silent and trimmable. Should have just done it myself in the first place! (Oh, ten minutes and I'm a TOTAL NOOB at derailleirs.)

My point: yes, OP, learn to fix your own stuff! You'll be so much happier in the long run, and so glad you did!