1) Fork over the $20k for a rust-free e30 m3 located in california.
2) Drive it back home
3) Buy an s50
4) rebuild/turbocharge the s50
5) Put the s50 in the e30 m3
6) Upgrade rims, brakes, suspension on e30 m3
7) Laugh as you destroy any new BMW at the track or on the street, particularly the new M3 which costs upwards of $60k. Be satisfied with the fact that you spent only $20k on one of the most coveted, pure BMW's ever built, and spent $15-$20k modding it to make it a unique performance monster.
Any e90 m3's pumping out 1000hp yet? Doubt it. Countless examples of e30's doing it... the e90 m3 is a great car for the modern american consumer (idiot). And before you flame me for not being able to afford an e90 m3 or some petty shit like that, I could pay for a maxed out one in cash today, (not with my parents money like half the shmucks on this forum), so, no.
Enjoy some pics/vids of a real BMW, and not a modernized japanese-toyota-looking thing with ipod integration and idrive and icantdrive amenities for the modern consumer.
