I have a wheel truing stand, basically a frame that you place your semi assembled wheel into with it's axle. It has a dial indicator that is used to measure runnout as you tighten the spokes. But I also use it to balance wheels. As you spin the wheel it will always stop with the heaviest part down. I'll mark that spot and spin it a few more times to make sure thats the heavy spot. I'll put a stick on weight 180 degrees from that spot and spin it again. If the weight was correct the wheel will stop randomly, if it wasn't enough it will still stop at the old "heavy" spot, and if the weight was too much that will become the new "heavy" spot. It takes a little trial and error but it works pretty gooder as they say in Nebraska.
If I had a shop like Steve I'm a thinkin' I'd have a professional balancer, probably more accurate and scientific, and would save a bunch of time....