Hi,
I'm in the same boat as you, only been playing for a few months now. Tried these programs for a while, and still have my bankroll online - never had any spam at all.
I bought Poker Tracker (55USD) and it totally covers my needs for the time being. Even for an amateur that just wants to play a solid game, it's a good investment. Only drawback is that it only tracks 1 kind of poker game (Omaha, Stud, Razz, Hold'em) for that price.
PokerStove is free, and gives you a good idea about your equity in specific hands.
Then there's a variety of HUD's (I think most depend on PT though)
-GameTime+ is free, very easy to use, but only offers very basic stats on your opponents
-Realtime is also free, offers a lot more stats, but I find it harder to configure. Not sure, but I think it gives a HUD in SnG's too, where GameTime doesn't. It's made by someone on this forum, and has it's own thread under "Internet Gambling - Software"(list on the left).
-PokerAce Hud costs 25USD, and offers the extra advantage that in some cases you get to see what hole cards your opponent played in the last hand. Only did a trial version, and I have to say I sometimes miss it.
Poker Grapher is the program most people use to put their results in a graph, and is also free (but limited to ring game).
So is PokerEV, while it's being beta-tested. It has the additional advantage that it shows if you're (un)lucky in all-in situations, and if you win/lose a lot of money before or on the showdown.
Software Forum Sticky
Hope this was of some help to you,
Fulca.