Originally posted by: StephenM
If you haven't seen one with all the exact options you want, just be patient and keep looking..it's a big enough of a purchase to wait for exactly what you want.
HOWEVER, if you've seen the exact car you want but they were asking more than you were willing to pay, you may have to raise you spending limit. NADA.com says the average retail on the car you described is $48,050.
EDIT: In the interest of being more helpful, here's a link to a traderonline search..
9 Blue 2003 M3s under $45k
If they don't have EXACTLY what you're looking for, you could try getting the missing pieces installed at the dealer. That is, upgraded stereo/Nav/Xenons may be dealer installed options...you could have them added after the fact. You'll pay through the nose, of course, but if you have to have it, you have to have it.
Also, try checking local big city papers. Most have their classifieds available online. When I was looking for my car I checked the ads for 4 different cities (all within a 2 hour drive) on a daily basis.