Logic
Pro Tools
Cubase
Digital Performer
Nuendo

There are a lot. They will all probably seem foreign to you at first though. I started out with Garageband too, and I was like "I want to do more" so I switched to Logic, but after a while I realized that GB isn't all that bad even though it limits you.

If you get ProTools you'll be limited by the hardware that it is compatible with, but it's the industry standard right now and most of the hardware is really nice (maybe a little pricey). On the plus side, if you wanted to track say guitar in your project studio and then go into a pro studio to track drums, your session would pop up just as you had it at your home. It's a lot harder to do that with other DAWs.

I like Logic because it's $500 with a bunch of other good programs and a sizable and decent sample library. It' also got great MIDI capabilities which I use. I think that what ever program can keep your work flow moving is good.

I've never really used DP or Cubase or any other DAWs.
This is where I let the really knowledgeable folks take over. I hope this helps.

Logic is a great program. Works with almost any hardware and comes with all the plugs you need to get your self going.
Plus the synth are top notch.
I have yet to find a better B3 emulator.