I have done lots of searching and still cannot find the answers im looking for:

Im thinking of buying some porsche d90's for my mk3 8valve.
they are front 7 by 16,and rear 9 by 16.
1/ will these fit my car
2/what size tyres do i buy(i like the stretched look on the rears)
3/im also buying coilovers,want the car lowered but not too much(as low as the local speedbump will allow me)

Yes this is my first post(virgin),and my first mk3 gti 8 valve,i dont know sh** about wheels and sizes,ive spent the last 2 days searching other forums,and im still not any wiser.
Your help will be much appreciated