its done all the time.
main advantage of a truing stand is you can see better, esp when you get down to the final adjustments, which are on the order of 3-5 thousandths of an inch (the thickness of a sheet of light paper). also, stands offer a big advantage in radial tuning IMO.
i can recommend the minoura truing stand for a budget stand. its not fancy, or sturdy, or has any fancy features. you have to flop the wheel around for dish, and the axle holders are sloppy (poor design, should have been a vee cutout) - i use brass shim stock to improve the fit. but it is a nice step up from building em in the frame.
nashbar has these. bide your time, use coupons. i got mine for $17.