Its not all that hard, just requires a methodical approach and some time and patience. Some photos, measurements and marking of the hub and rim before you start can save a lot of frustration and anguish when putting it all back together.
There are a few articles on the net on how to do it. For truing up I just mount the wheel back into the swing arm and use a dial indicator or pointer, usually getting the offset and axial runout first the the radial runout.
A good spoke spanner helps and they are on ebay as a kit to cover most nipple sizes.
With old wheels rusted on nipples is the biggest problem. A little bit of heat helps as well as WD40 etc. Broke a few spokes on the Husky wheel and had to get some made.
If your a serious racer I'd say leave it to the pros, but for a bike thats not going cop a lot of use/abuse and you've got some time its a cheaper alternative for sure.