Short on cash $$$$$$

At this point the only thing I own is a 2000XL & a PC with a sound blaster live sound card installed and sound forge 6. I wanted some suggestions on what I could purchase next to get the most out of the little I have I have a couple Hundred bucks to spend ( $400). I had been hearing about a mic pre amp or compressor what are their purpose and could I use them I had also been thinking about some sort of effects module something decent but inexpensive or maybe a little 4 or 8 track recorder or maybe another sound card for my PC I would really like to get it in the beat making mix. Just looking for suggestions.

Get a mixer.

what kinda mixer and how and what can it be used for I'm new at this!

What exactly are you trying to accomplish? You could do a few things with $400.

Mixer - seperate your channels, not reaaly a necesity if you don't have 8 outputs unless you use it to sample sounds.

A Sound module - a proteus 2000, or Mo Phatt, Roland, and a few others can be found for under or around $400 on Ebay.

A nice turntable and some vinyl for sampling
A multi track recording program i.e Acid 4.0, Sonar 2.0, Adobe Audition, etc

If it was me I would get a keyboard controller about $150 and a nice sound module about$250 sequence into the MPC and record to Soundforge.

My setup consist of:
MPC 2000 XL
MPC 60 Mk 1
Behringer UB2222 (under $400)
Mo Phatt (under $400)
Roland SC-88 (under $400)
Kawai K4 keyboard
Midiman 49 key controller (under $400)
PC programs
-Sound Forge 5.0, 6.0, and 7.0
-Acid 4.0
-Adobe Audition

hope this helps,
D James

Whatever ever your needs are for, Mixers "Mix" sounds (i.e. MPC, keyboard, voices)... Or you may just need a simple 4Track recorder with mixer functions, go with Zoom or Roland. Those are priced around your budget, but this topic is in the wrong post. Check out studio environments.

hey hey! Hold on here. The kid doesn't even have any other gear and maybe not even 8-outs. What's he going to do with a mixer?

Let's focus on what you have right now, and what you're trying to do with it.
1.What kinda music do you make?
2.Do you sample a lot of stuff yourself, and do you feel you have enough sounds to start a new track every day?
3.Would you consider doing a lot of stuff inside the pc in the future, or would you prefer a lot of hardware gear with knobs?

I think it is too soon for a mixer and would go for maybe a keyboard controller or a keyboard with good built in sounds(can still be used as a controller ).
I would max out the ram in the MPC. cost like 10-20 bucks, but very important.
You don't say if you like sampling records or samples cds or anything so it is hard to know what to recommend cause we don't know your style.
A zp drive for the MP is always a good option.
Need a little more info to really help.