The race teams use purpose built computers and data loggers. Some also include telemetry to broadcast info back to the pits as the flog it around the track.
B&G Performance has some good tunes that they will flash to a PCM. You pick the tune, send them the PCM (I'd pull one from a upullit junkyard for a spare) and they flash it for ya. They do have some options based on what you are looking for, i.e., low end torque for heavy towing, over the road mileage, mild performance, etc... They can also program a PCM for, say, a Magnum 360 that has become a 408 stroker for instance.