I have used an ADVC55, setting the camera to clip the 16x9 to 4:3 and component out. There are far better solutions but this low cost one works very well and requires no installs or drivers on the computer.
COMF5.com is an amazing service for streaming and many other things and is dirt cheap for the bandwidth and storage... $40/mn.
You have no ads and can easily host on your own page... again... no ads or pop ups.
With the free services, you can use Livestream.com or Ustream.com (and others). Each of them have their own client for uploading or you can use Adobe's Flash Encoder, which is free. It creates a nice stream but is a bit more complicated.
I and my cohorts have used the above extensively with great stability.
