Seconding Fern's comment... budget and goals are everything. You can get decent amounts of power with less than $1000 and a bunch of DIY know-how, or you could go crazy like I have in the past and drop tens of thousands on a nice setup. Since you bought the car for $1200, I'm going to assume that your goals are pretty modest.
For a street racer (which we don't really condone around here), you could drop in a D16A6 or any other non-VTEC D16 from 88-00 and wire it up with an MPFI conversion (search the terms) and a PM6 ECU for just a few hundred bucks, then junkyard turbo the engine with an HF/STD manifold and one of the zillions of DSM TD05H-14b or TD04H-13g turbochargers laying around.
Doing all the installation and tuning by yourself (not super simple, but still easy with this setup in comparison to quite a few other paths you could take) can easily put you close to 200whp on pump gas. The whole setup- engine, turbo and tuning- could all be done for under $1000 if you know where to look for parts and are willing to put in the time and effort.