Soundcard - use onboard unless you're unusually picky.
WIFI - Netgear or linksys usb adapters work fine. Or you can get a PCI one like i have with an external antenna.
GPS - I use a bluetooth USB nub that i got from Newegg for cheap. I have a bluetooth GPS that i got from buygpsnow.com for like $50 USD. They might ship internationally.
Problem - Make sure centrafuse can read your music format. AKA it wont read AAC (mp4) unless you upgrade the bass file in the directory. You can search that on the forum.