A great place to look for parts is Bimmerforums. People are always sellign the stuff you are looking for. Headlights and that M3 bumper and basically everything. Ive seen some cheap CF hoods on bimmerforums go as cheap as $100. Some decent ones you might find used or even new for like $400. So if you shop around on Bimmerforums here is what i think you could get at what price
CF Hood - $200-$300
M3 front bumper (new) - $400 - look in group buy section
OEM Headlights (used) - $50 - or maybe even new. plenty of people sell their used ones when they upgrade to Projector headlights. You could even pick up some semi-cheap Euro projectors for like $130 on www.jlevisw.com
Fog Lights (new) - $70 - ZKW or DEPO's or OEM are basically all the same price for fogs
Corner Lights clear - $40 or corner lights used amber for like $15-$20
None of this includes paint. Your car is black so you could easily get away with an unpainted CF Hood.
Hope I didnt miss anything