I have a 1995 trans am with the following mods...
K&N intake
.373 gears
long tube headers
offroad y pipe
catback exhaust
shift kit
PCM tune

what kind of cooler should i get? theres all different power ratings and i dont know which one is most suitable for a daily driver that i will take on the track occasionally

 

The biggest you can get. I think 28,000 is the biggest, and that'll be plently.

 

I have the 19000 gvw it fit pretty good in front of the radiator.

 

are these really hard to install? and what tools etc. do you need?

 

They are not that difficult, it should only take an afternoon.
B&M makes a kit, 70264, that contains all the parts you will need (bolts, brackets, hoses, etc.) that has a 24,000 GVW rating. It functions well, is reasonably priced, and very complete.