searching for undervalued cards

I drafted Marrero based on this thread, and have been thrilled so far (5 HRs in 9 gp). I was wondering how you found him in the first place--did you go through every single card, or just notice that his HR numbers would extrapolate well to an entire season.
For the rest of you--how did you find your most valuable cards?
Also, it looks to me like there aren't really many or even any pitching bargins the way there are with hitters.
For the rest of you--how did you find your most valuable cards?
Also, it looks to me like there aren't really many or even any pitching bargins the way there are with hitters.