Hey dude, ive got TEIN HA coilovers on my ZE ae93 with 24 point adjustable dampening rate, and camber tops.
Coilovers are the best thing I have ever bought for my car, the increase in response and drivability is nothing short of enlightening..go for it!
--- camber ---
From my experience there are 2 main ways to go about it.
1. Camber bolts
2. Camber tops
Camber bolts are replacement bolts to the ones that attach the bottom of the suspension strut to your wheel hub. They have a lobe on them that when rotating the bolt, pushes the wheel hub toward/away from the strut allowing a limited ~2 degrees of camber adjustability.
Camber tops which come on many coilovers allow you to effectively grab the top of the suspension strut and slide it left or right to increase/decrease camber by large amounts. Its much easier to adjust as you don't have to take off wheel and fuck with high tension bolts. Be careful though because if you go crazy with negative camber (like i did when we first put coilovers in) the front wheel toe-in increases dramatically and you will shred your front tyres before you make it to the supension place for a wheel alignment
--- spring rates ---
Coilovers on the second-hand market have quite varying spring rates and this choice is critical for getting the right balance for street driving. My corolla is ~1200Kg and i have 6kg/mm springs at front, 4kg/mm springs rear. This is already stupidly solid. Even with a heavier car like a soarer I would try to stay below 8kg/mm Front, 6kg/mm rear.