stock 01 ssei people, lets hear it!!

hard to say.....every single car on this forum is different, and there is no magic formula to determine pulley size

do you have a Scanner??

if so you might want to Try a 3.4, but you NEED to scan for KR
if you dont have a scanner try a 3.5

you need to scan the car eventually for KR regardless

a scanner? whats that <--- stupid.

where can i find a good one and for about how much??

One important question you need to ask yourself is; How far am I willing to take this car mod wise, and how much am I willing to spend to get there?
A scanner allows you to see how the engine is running. Allows you to see what the PCM sees to regulate your power train.
Most members would recommend the aeroforce scan gauge. do a search for it and you will find more than plenty of posts about it.

By pulley size we mean the size of the pulley at the end of your supercharger snout. Your all supercharged series 2'* have a 3.8" pulley from factory. Before you even think of dropping sizes, first give your car a "FULL TUNE UP" (I mean everything). You need you car running in tip top shape before you start modding. Then get a 180 degree thermostat, one range colder plugs (NGK TR55, or Autolite 104 in copper), a cold air intake/ fender well intake, and maybe a high Flow catalytic converter. Then you can safely drop pulley sizes as long as you have a scanner! Every motor reacts to mods differently. So to be safe some would recommend a 3.5 pulley to start (with basic mods), but some have been able to run a 3.4 safely at that mod level.