Everything that you have may be M-Audio, but what do you have? Do you already have an audio interface? A midi controller? A midi-sport? Monitor speaker? M-Audio makes a lot of different things, from interfaces to mics to preamps to midi controllers...
Here are some brands anyway.
Audio interfaces: RME, MOTU, Digidesign, Presonus, M-Audio
Midi Controllers: M-Audio, Novation, CME, E-MU
Mics: Shure (SM57, SM58, SM7b), EV RE20, RODE, AKG,
PreAmps: True P-Solo, Grace 101, FMR RNP, M-Audio DMP3 and Tampa,
Accoustic Treatment: (Start with bass traps) GIK Acoustics, RealTraps, DIY
Thats just some stuff off the top of my head. If you are a bit more specific of what you have, what you want to do, budget, etc... we can point you in the right direction.