Originally Posted by peon402
I've never been the most confident rider out there, but have generally been able to stay upright and avoid crashes. I started riding again last year after a 10 year lay off and descovered I could no longer descend! As I live in the mountains this is something of a problem. The bike seems ok, no obvious wheel or headset problems. As I pick up speed the front wheel starts to violently shake. I think I'm so nervous that I get a death grip on the bars that starts the problem and then makes it worse.
Today I had the same problem during a high speed sprint on level ground. Is it me, the bike or both? I would like to get back to enjoying my rides instead of worring about crashing. Thanks, peon 402.

It could be something on the bike. It could also be that you are holding on too tightly. I'd ask a shop to look at the bike, and you could also see if anybody around has some bike handling classes. My guess is that it's more you than the bike because of your description of nervousness.
There are some drills you can try here:
http://active.com/story.cfm?story_id=12675