I've played music all my life but I have never recorded anything or done anything on the computer with music and I would like to start. What I will be doing is doing soundtracks for small homebrew games im creating. I would like to connect a keyboard that has programmable keys that I can map for different sound effects/instruments. Here is the system that I came up with:
-iMac 24inch maxed specs (ram thru crucial)
-logic express or garage band (I havent used either or owned a mac, im new to all this)
-keyboard (I would love a suggestion on this as I havent keyboard shopped in 15 years, and I cant run to a store to see what they have to offer)
Am I on the right track or am I way off track? Any suggestions or advice would be most welcome

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For starting out, I think the iMac will work fine. You don't really need a Mac Pro unless you're doing a lot of sequencing at once (like an entire orchestra). If you get 4 gigs of ram you should be set for awhile.
I would recommend playing around with garage band and then getting logic express and then upgrading to logic studio (in time).
As for keyboards. I've got a few points:
First off, you're looking for a controller keyboard. You have a lot of selections for controller keyboards these days. They usually come in 61 key, 76 key, and 88 key versions. You can get smaller key versions but I have a hard time recommending them. Secondly, you're going to have to decide if you want weighted keys (like a piano) or synth keys (like a synthesizer). If you're a piano player, I recommend getting a weighted key controller.
These days, a lot of controllers come with usb connections as well. But most audio interfaces have midi ins so you can simply connect your controller to the audio interface which connects to the computer. Also look for slider/knob controllers on the midi keyboard so you can control certain parameters of your software with it (such as panning, volume, modulation, etc)
Controllers I recommend:
- The M-Audio keyboards are good for beginners. Their weighted keyboards feel cheap though.
- Edirol (a division of Roland) makes decent models that I find more high quality than M-Audio's.
- If you want a weighted keyboard, I have only been able to find one keyboard that is satisfying to the touch. And thats the Fatar/Studiologic vmk-188/vmk176/vmk-161. I own the vmk-188 and it is the most spectacular feeling controller I've ever played. When playing this keyboard with Synthogy's Ivory Pianos, it actually feels like I'm playing a Steinway. Has plenty of knobs and sliders too.
Check musician's friend, sweetwater, and zzounds for keyboards. They have a bunch of em listed
Good luck with your studio!