I use Leakbuster, Flopzilla, Notecaddy, HM2, Bovada
HH Converter, and Holdem Indicator for a HUD on Bovada. Been messing around with Pokersnowie also.
So those are just a few of things that are out there. i'm not sure what stakes you are at , but the small stakes version of Leakbuster should be good up to 50nl. . The new version is supposed to be out in a couple weeks, and sounds like it has some nice new features. It is one of the first things i got when i started playing cash games, and it has helped me. Flopzilla is $35 but is well worth the $. There are some good tutorial vids on youtube about it. so maybe check those out and decide.