The sabermetrics blog on here is pretty good as well.

Heres a good beginners primer: http://www-math.bgsu.edu/~albert/papers/saber.html

Most of the stuff you’ll pick up as you go along.
Part of it too is knowing what you want to do. If you just want to understand what people mean when they say something like: Yuni’s BABIP was low last season but his LD% was right on, so we would expect regression to the mean and an increase in WAR though that doesn’t help his bad +/-. Then you can probably just use fangraphs glossary.

But if you actually want to calculate your own stuff then check out sites like Baseball Prospectus, baseball-reference and probably some other sites I’m spacing on.

http://www.royalsreview.com/2010/3/5/1358354/place-to-ask-potentially-stupid

I appreciate your help.

here’s a good one that incorporates a number of them. Perhaps start with the section on “sabermetric principles,” although this also contains primers on a lot of new stats

http://saberlibrary.com/

www.treytoneducates.com