I dont know much about gaming headsets... or headsets in general...

I want a 5.1 headset that will work on a tv/my 360 and ps3

Is it possible, i have looked in a lot of places and i cant get any info on any headsets...

How much would they cost? Where can i find a pair? And most importantly, does anyone have reccomendations?

you can only use 360 headsets on 360s, im not sure about ps3s, i donno about pc headsets, one with a mic? i just bought one without a mic for like 30 bucks, an apex hp-40, it gets the job done, its not that good, i got at a local music shop.

ok, but what about my tv, can i use a headset instead of the speaker output?

yes you can - I would look at some DJ headphones for the best quality sound though they can be a little bass-heavy

Sennheiser headphones are the shit though if you can afford to splash out on a pair do the sound quality is superb - though don't expect even simulated 5.1 without a USB port.

I wouldn't worry about "5.1 headphones" any headphone that has that feature is just pure emulation. You would get much richer sound from professional stereo headphones.  As the poster above me said a couple of DJ headphones would be great for you.

Here's a good midrangeheadphone

and a good cheapheaphone

I have a pair of Sennheiser HD555s that I use for playing Halo 3 and listening to music, and they're excellent. Most all Sennheiser headphones will be of good quality, but those in particular are excellent for gaming (of course, if you're playing on Xbox Live, you'll need a seperate headset to communicate with other players).

If you feel like spending a ridiculous amount of money on a "pro" headset you could check out the Astro A40 (search google).  I wouldn't recommend it personally but hey it's an option.