They sell those at Dick's Sporting Goods, and yes, they are reasonably priced. I've seen them go on sale several times.

 

You also might want to think of putting the camera mount on the bike itself. Like on the bars.

 

I posted a video I filmed using a camera mount I built I shimmed the camera angle with two pennies and a nickel. It still didnt point UP high enough so I had to ride damn near looking up in the sky. Which made for a lame ride video cause I couldnt let it RIP looking too far ahead to see what was in front of me

 

I just bought a GoPro Standard camera and so far I think it is great. it comes with several mounts and as far as I can tell it works great. It does not seem to work real well in low light but for what it cost I think it was a good deal

http://www.youtube.com/watch?v=Q0Qimfqu4M4

 

Problem is the bike bounces around too much and the video comes out like crap.
Your head stays relatively still.

 

I didn't know that...good to know.