PokerTracker

I just downloaded it and configured it for Absolute Poker, but it's not even listing tables.

Are your hands importing? Are you using PT2 and PAHUD or PT3?

Can Poker Ace run on it's own without Poker Tracker? I don't have poker tracker

No, PAHud gets its information from a PokerTracker database.
If you don't have PokerTracker yet then you will need to try the 60 day free trial of PT3 instead of trying to use PAHud, as PT2 is no longer on sale.

Download page
Documentation

It finally just popped up with a bunch of N/A and then when I changed some of the filters, it left again.

So this purchase will actually cost me $70 if I don't want just the trials?

PT3 is $89.99 (including the built-in HUD), but if you are not located in the United States, we have several FREE PokerTracker 3 offers simply by signing up and playing on Mansion Poker (iPoker), Titan Poker (iPoker), Poker Ocean (iPoker), Pacific Poker (888), RedKings Poker (OnGame), or NoIQ (Entraction).

PT2 is no longer on sale, and PAHud only works with PT2.
(The omaha and stud versions of PT2 are still available as the omaha module for PT3 has only just been released.)