AuzenTech Xplosion or HT Omega Striker
 

AuzenTech Xplosion - $85.85 - NX Source

HT Omega Striker - $68.88 - TD Direct

I can't decide between the two.

Same here :P

I just want to hear every footstep in CSS and other FPS :haha:

They are pretty much the same card from my understanding but one is only 24bit while the other is 32bit I think or something like that.

Grab the X-Plosion. Will give you options for updating the opamps. -Which is a plus. Both cards are based around the same chipset. This means they will offer the same features and most likely same software and drivers. The only difference will be in the components used for the input, output sections and filtering components. So, grab the X-plosion, I know a few guys with those cards and they like them very much. Grab some new opamps also and you will be good to go.
Both cards are 24 bit though. If your really into gaming I would suggest other cards...

I listen to music and game with mine and I'm pretty impressed with it. Its pretty bizarre hearing noises come up from behind you (5.1 setup properly)

Rob, I'll be using it for gaming but I want to stay under the $100.00 mark as my budget for this rig is getting tight and I want something better than onboard.

What I am saying is the X-Plosion only offers EAX 1 and 2 through software. That is all you get for gaming. Mind you, it is a great card from the analog quality perspective. Just make sure you know what your getting. Let us Know what you get.