GoPro prices are pretty much the same everywhere, unless you want a risky eBay purchase. I got mine from Tweeks having realised a 10% off voucher I had for something could be used.
They are excellent and very easy to use, some good alternatives are out there too now.
Look for danzaproductions on the tube and you'll see my trackday footage. I don't use the waterproof case, which will explain the slight wind noise at 90+, it's too quiet otherwise