Motec is a small exhaust maker made famous by Fast and the Furious movies. MoTec is a very large engine management EFI company that make ECUs and other automotive electronics for the aftermarket industry, race cars and some limited OEM (Porsche is one, they fitted them to the GT3).
MoTec is a company that makes car parts. Most of their products deal with engine management and merchandise related to cars and engines. One can find an online catalog at their website.
It all depends on what modifications the car has. If it is stock standard (untouched, how it comes off the showroom floor) they are quite a very nice car to drive/maintain. Your basic servicing can easily be done through you Subaru dealership. As for maintaining a modified Subaru (90% WRX's/STi's) it can be costly. Obviously if you are putting performance (also known as aftermarket) parts into your car, and using them for driving hard/motorsport, you will spend alot of money. Eg. Putting a bigger turbo, tuning it, and a heavy clutch, and redline launching, of course you are going to break gearboxes and fry clutches. There are a range of aftermarket ECU's (computers) available such as a Autronic, a Link, MoTeC etc. These are usually fitted with/or after modifications such as a turbo upgrade, fuel system, exhaust, front/top mount intercooler, injectors etc. What ever you wish to modify your car with, remember you do need to change your oil, check your compression, check your brake & clutch fluid and keep a eye on your air/fuel ratio's. Any aftermarket parts, in my point of view, if you aren't knowledged when it comes to cars, take it to a performance workshop. Have fun!