Mac mini March: Where to get parts for your Mac mini
Accelerate your Macintosh has listed where you can acquire Mac mini components, if you happen to be one of those fun-loving Mac mini hackers who told Apple to ship you the bare bones unit and you're looking to maximize your mini. Evidently, both Airport and Bluetooth mezzanine boards and antennae are available via cgnusa.com. Each antenna is listed for $29 a pop, and the boards run $59 a pop.
At these prices, it might be better to order your Mac mini with Bluetooth and Airport included; however, it is good to know that people who have already bought a mini have an option to add these interfaces after the fact. Here's
another page listing all the Airport / Bluetooth parts you'll need.