My 2006 330i was $44,920 before taxes.
A similarly equiped 2009 328i runs for $45,375
A similarly equiped 2009 335i runs for $50,675
The 2006 330i is roughly the same price as the 2009 328i (is almost the same performance too - the 255 HP vs 230 HP is not that noticeable). Although for that price the 328i comes with 17in wheels and not 18in.
The 2009 335i is more almost $6 grand more than the 2006 330i. The 335i is a lot more powerful though, and has more flexibility on tuning.