Fair enough; coilovers probably are the right choice in that case.
This is not my area of expertise; there are a couple on the market at the moment.
D2 and
BC... one of them is more recommended than the other.
Once you've got them, take a look at Campbellju's mod to use the top plate to give you more camber.
There's nothing in unprated wishbones etc. - All you can do is polybush them. From memory SuperPro/Superflex/Powerflex/Energy Suspension/Whiteline all make bushes for the wishbones and droplinks. Whiteline might be the only ones that do one that adjusts the castor a bit.
It's probably worth finding your local Whiteline dealer; around here it would be Demon Tweaks.
The steering rack bushes are elusive. - Energy Suspension may or may not make them; the ones they sell may not actually fit a GTiR.
There are a couple of people who make kits for the rear sub-frame I think.