you need to have a look around in the turbo section. TON of info in there.
something else that may be cheaper, though i don't know much about the wiring aspect of it...would be to toss a cheap realiable engine in there and get it running. such at the 22e. would give you a nice little bump in power along with some extra torques. then if you feel like you want more, throw some boost at it. which, there are threads in that same section along with a few in the member journals section that outline it all pretty well with do's and don't.
for reference: my car came stock with the 22e. i put some boost on it for pretty cheap, ~1600 bucks. at 11psi (max for this styler maf) it will just about keep up with stock 15+ WRX's. as in, they only pull away once i shift out of third.
there's also all the other swaps out there. ej20g, ej20k, ej205, ej255, ej257 etc. though, the further up you get in displacement, the more money you spend. also, plenty of threads in the turbo section about the pro's and cons of each.
happy reading.