Stookin, I would not recommend spending the time and money for an S54 Swap. There are a lot of shops around the WHOLE USA that can do the swap. I actually think you'll be better off in the West Coast. A lot more bimmers out there than here in the East. A 2001 330i is worth about $10,000 if it has under 100,000 miles + 8,000 of the motor swap you were planning on spending, and that's $18,000. More than enough to find a a great deal on a 04-06 M3. Plus you get better handling, better suspension, better interior, and the mindset of owning a genuine M.
If not, you can easily get an Mtech 2 kit, upgrade all of your maintenance items, exhaust, chip, intake and a lot of other mods...all under $5,000 and still have just as much fun as an M.
I would consider those two options.