I do my own maintenance on most of my bike, and it sounds like your rim needs some cleaning. I usually get that squeal when they are dirty, or if I have adjusted them when they wear down. Mine easily adjust with (patience) and an allan key, so I use the trial and error route and do minor adjustments. They might just need to be washed off though (the rim)
Oh ya, we are talkin' v-brakes right? Discs are a whole other world that I will learn next year!