I'd say your next step is to either cop a keyboard workstation or similar "deep" synth with sounds you're not going to hate in 3 months. This will give you a huge pallete of sounds to work with and once you've exhausted that supply you'll be able to synthesize your own sounds.
I recommend buying a workstation over a modelling synth only because it's hundreds of real-world sounds (in addition to out there stuff) rather than crazy off the wall sounds. Sure you're gonna want off the wall sounds but youre also gonna want those straight sounds, and you'll need more of them more often.
If you go the hardware route rather than the software route, you're going to need a mixer. Get either a small mixer if you plan on keeping your harware gear to a minimum (think 4 channels) or a large mixer from the start so you can pop your gear in whenever you pick up more.
Regardless of which path you take, you're going to need decent speakers. Read up on what everybody thinks of different units. I use Event TR-5s, love em.
If you go the software route, be sure to try out demos before blowing hard earned cash. If you don't like the sound, the interface, or any element of a program, move to the next. Soft synths are far cheaper than hardware, but it still seems ridiculous to spend hundreds of dollars on a little box with a CD on it, even after all these years of computers being around. Soft synths can create any sound a hardware synth can create, don't let anybody tell you otherwise.
If you're already walking down the software path, cop a nice sound card, MIDI interface and (if you can afford it) grab an audio interface. The Yamaha 01x is top of the line here, you can use it as a stand alone digital mixer or as an audio interface to the computer with nothing but a firewire connection. (no processing done on the PC, no other soundcard needed) I'm running a Roland SI-24 and this is good enough for me, so far. 8 ins so I can pop in my MPC, Karma and rack sampler, and I can FINALLY sequence soft synths via my MPC.
Be aware, though, that recording audio and using soft synths requires LOTS of memory, a beefy processor and you really should use a second (ulta fast) hard drive.
If you're a technophobe who shies away from getting deep into computers, you might not want to go the computer route.
So far I've discussed production using either a mixer and hardware or a mixer of sorts and software. What I haven't covered is recording proper.
You have three options when it comes to recording. (well 4 if you want to count shitty outdated tape recorders) Outboard recorders, Multi-trackers, and software.
Outboard recorders like DAT and CD Recorders are mostly for people who don't want the hassle of dealing with a multi-track or learning software. They range from extra cheap (300, 400) to real real expensive (1000 and up) They're generally simple in that you run your stereo outs from your mixer straight to the recorder, hit record and go. Some are more complicated, entailing sync options like word clock, SMPTE or other mumbo jumbo. Some outboard recorders have multiple ins and are essentially multi-trackers without the faders and EQ/dynamics/onboard effects.
Multi-trackers are the middle line (in my mind) between bulky mixer-gear-recorder setups and confusing, learning-curve-intensive software setups. They're generally a breeze to use, have tons of features and are quite portable compared to the other setups mentioned. A multi-tracker with enough ins eliminates your need for a mixer entirely, eschewing this responsibility to the mixer controls of the multi-tracker itself. These units can get costly, however, with units ranging from 300 bucks for a 2-in recorder to 3000 bucks for 16-ins recorders with touchscreens and flying faders. Then there's the predicament of "do I master on the multi-track or do I take it move it to software" and that adds another step to the process.
Software recording is becoming more and more viable as computers get faster and more able to deal with several tracks of sound coming in to them. Recording software is NOT cheap though, ranging again from about 300 bucks to LOTS of cash. If you can get software that's not limiting that comes with your audio interface to your computer, stick with it unless you've got the cash. (I'm using Logic now since it came with my interface) However, as I said you need a SERIOUS computer (as long as you soup it up a bit, any cheap machine from the past year or so will do, but off the shelf it's no good) and you need to get down and dirty learning the complex process of multi-tracking in software, possibly integrating your soft synths in this composition/recording process, and this takes a lot of time.
So there's a few different battle plans for you, golden_child, and good luck.
Know this though: Music gear aint cheap. I've spent thousands of dollars over the last 3 years since getting interested in it, and you gotta be willing to spend if you're trying to do more than bang on a box in your bedroom.
That's not to say you can't just do beats on your MPC alone, but if you're looking to expand, as you say you are, there's a huge world of techniques and tricks ahead of you.
Peace.
-tank.
You don't know what I know
Cuz you aint seen through my eyes
This spliff is always lit but it's a natural high
http://www.dcbeats.net