And for suspension - are there any ways to lower the car other than different springs? Every vehicle is different is why I ask, my Tacoma is lowered in the front by moving the mounting position for the balljoint, which in effect moves the spindle up higher, but uses factory shocks.
I don't really like using springs that make a large change to the vehicle's rideheight, it screws with too many things. Coilovers are a far better idea as they correct many of the problems you would encounter with only coils.
There are two different styles of coils, progressive rate and fixed rate. Progressives are alright so long as you don't take turns too hard. They are designed to have different spring rates depending on how hard they are pushed, the harder you turn the stiffer they get. What this means is they ride alright when just cruising, but if you start to turn really hard they change how the car handles and can surprise you. Fixed rate springs are better for road racing, as there are no surprises. This is just another thing to think about.
Coilovers are cool because there are sets out there that let you adjust how stiff you want the car depending on how you plan on driving it, without being a progressive spring (no surprises).
Sometimes you can have as much, or even more fun with a car that handles great than a car that's straight line fast. I'm working on a fiero now that has a 90hp engine and won't be getting any engine mods anytime soon. I'm going to get it running, do a coilover suspension, upgrade the brakes and get some good tires, and it will be done. I may do an engine swap at some point in time, but that's not happening right at the moment.