How can I adjust for uneven brake wear? Well, my problems with brakes have turned out to be not an issue with pad longevity at all -- see the following picture:



Note how the one pad is excessively "toe-in" worn.

Here's a picture of the brakes they came off of, with the parts labeled as far as I know them (with the new pads I just put on...):



(Erm.. that should say "Centering Adjustment Screw" ... hooray for tpyos!)

I don't see any way to change if the pads are toed in or toed out... how can I fix this (is it even possible?) ?
There's two ways to adjust the toe in. The metal pad holders that are the other half of the brake pad assembly should have some semispherical washers in them, allowing you a few degrees of adjustment. Loosen the bolt that holds it on, jiggle it to free up all the pads, then squeeze the brake lever to pull the pad against the rim and get the alignment right. Using a wee bit of cardboard or something between pad and rim at the back to set the toe in, of course.

The other method is to carefully bend the caliper/brake arm. Obviously it's much better to use the previous method, but if that's not an option, set an adjustable wrench so that it fits tightly onto the slotted part of the arm (just above the brake pad), and twist the arm to a better position. Careful is the word - much better to have to tweak it three or four times than have to bend it back if you go too far.