get any soundblaster soundcard
NONONONONONO DON'T get any soundblaster card at all if you are buying a card for music. They are good for games and movies. Not audio.
There are way better audio production cards out there for way cheaper. I'm not just jumping on the anti-SB bandwagon here. I have one and it cost me a few hundred quid. It's crap for audio. Seriously, don't waste your money unless you want one for games and movies. I bought an M-Audio Delta 44 for £90 and it's a vast, vast improvement. I can't totally advise on the variety of soundcards, as I only have experience of my Delta 44, but it's pretty good for the money. Also do a search on this forum. The subject of soundcards pops up a lot. Just don't get a Soundblaster.
As far as software goes, check out Audacity (free) or Reaper (nearly free). If you want to spend more money on software, Cubase is good, Adobe Audition is good. Ableton Live may well be excellent for your needs. A lot of it is just down to personal preference and how you work. Personally I prefer Cubase. Others prefer something else.
I personally wouldn't fork out for ProTools, as you may find there are limitations (such as a track limit) that you end up having to spend more on to unlimit. It's a bit of a money trap. As Nu Krimson says, ProTools will also only work with Digi hardware, or M-Audio hardware if you get ProTools M-Powered.
You can get software synths, which may save you some money. There are a lot of awesome free and non-free synths, plugins etc on
www.kvraudio.com. All of the plugin and synths I use are free, and some of them are awesome. As far as the micron synt goes. I know nothing about synths, but the best way to find out if it's any use is to try it out.