It really depends on what you want to do with it. Is this just for fun? What budget? Do you want to be able to record live drums (big one)?
Really, it all depends. I have A LOT of gear, but I do this professionally (engineer/producer).
Basic recommendation?
- Good audio interface known to be stable: Apogee, Native Instruments, M-Audio, or Focusrite. I tend towards Apogee, but they are a bit pricier. If you want to record drums, you'll need MINIMUM 4 mic pres. The Ensemble is the best currently available 8-channel-with-pres interface, IMHO. If you just want simple, I like the Duet and the NI Komplete Audio 6. I'm not a fan of Avid's stuff, but it has gotten a lot better.
- A good DAW/Composition program: don't bother with Pro Tools if you are just a hobbyist, way overkill and more difficult to use than Logic, Cubase, or Ableton - GarageBand is fine for basic stuff, too, and Reaper is cool for cheap if you don't mind dealing with its idiosyncrasies. Personally, I use Adobe Audition (as a sample editor, mostly), Ableton Live 8 (for composition and sample/VSTi stuff), PT9, and Logic 9 the most. If you are into sample-based music, really check out Ableton - it sounds only OK compared to Logic/Cubase/ProFools, but it is MUCH more intuitive, especially to a neophyte. It is also dead stable, while the big three all have their crashing issues.
- A few good Mics: look for used Dynamics, and pick up at least one cheap SDC and Ribbon. The Shure KSM137 is an awesome SDC that works for a lot of things, and is cheaper than many inferior mics. Don't bother with LDC's, unless you really want to spend money and time - they aren't as friendly. As far as overall mic-must-haves go, my recommendations would be: Blue Encore 100i (less congested SM57 sound), Beyerdynamic m160 (super-versatile ribbon that works on anything), Shure KSM137 or 141 (two of my favorite SDC's, and cheap), and an EV 967 (dynamic with a brighter and faster response). Those are all cheap and (other than the Beyer) easily found used. You could spend $100k on mics and not be happy, and I have, and those are the ones I use the most that are not $$$. Honestly, the Beyer (well, I have 2, and an m130 for m/s) gets used more than any other mic I own, because once you learn it, it just works on almost anything.
- Controllers: depends on what you want to do. Honestly, I have A LOT of controllers, from Keyboards to Pads to Mix Consoles to DJ gear, and I use almost all of them regularly for different things. Best bang for the buck? Unless you want to play Piano - in which case, god help you, because there are NO good 88-key weighted midi controllers out there - the Akai MPK Mini is about all you need. Good pads, easily assigned knobs, and a decent little keyboard for sketching out ideas. I have Novation, Akai, Nord, and M-audio controllers around - full sized, mind - and the Mini gets used more than any other. I bought it to use on airplanes, honestly, but now it just sits next to my MBP and gets picked up all the time! If you NEED full-sized, I like the Akai and Novation controllers best for the money - I personally use a 61SL MkII, and am borrowing an MPK88, and both are quite good - though I've heard mixed feelings about the Akai's keys, which do tend to be stiffer than other offerings. I'm not a fan of the M-Audio's (have an Axiom 25 gathering dust somewhere), because they are MUCH harder to program, IMHO, than the others.
- Monitors and Headphones: don't overlook this! I recommend, for band for the buck, the low-end KRK stuff over anything else, by far. Look into the Rockit 6's (stay away from 4" drivers, unless you LOVE midrange) and the 8400 headphones (just a warning, they need breaking in!). There are lots of other options out there, but those are the ones I use for clients who are on a budget.
- Final Recommendation: Pick up an Apogee Duet 2 ($600), Akai MPK Mini ($100 or less), Blue Encore 100i ($75 or less, look around), Shure KSM137 ($300), 2xKRK Rockit 6's ($300 total), KRK 8400 ($150 or less), and the requisite cables ($100 or so). Those are all NEW prices, and not even good deals. It may seem like a lot of money - and you can certainly make music for less - but this is IMHO the minimum for QUALITY (as in, little to know compromise) equipment that will last you a long time. I own all these, and use them regularly alongside my $$$$$$$$$ stuff. Oh, and I forgot to mention, get either Logic 9, Ableton SUITE 8, Reason 6 (though I'm not a huge fan), or NI Komplete 8, if you want to MAKE music and not feel limited by your software instruments.
You don't have to get everything at once - it is around $2k or so - but I do suggest NOT CHEAPING OUT. You'll just get frustrated, and creativity will suffer! Start with the MPK Mini and the headphones - though the Mac audio outs SUCK - just to see if you really want to put the money into doing this. The cheap stuff tends to not work well, nor get along with others - and the price difference with the good-enough-for-pro-stuff is such that you may as well go for the good stuff!