I use an archaic datalogging program from Palmer Performance (PCM Scan Pro), which enables me to log everything the big $$ programs do. Yes, it's not the uber-expensive, big dollar system money-bags Steve has, but it gets the job done.

My cost for the software and OBD-to-USB cable was under $200. In all honesty, I did send them a check I filled out with a crayon. That's all I had at the time.