This is kind of risky business... but I have used this software before. There are a lot of places that offer a service to host your cam, but this actually takes your pc and turns it into a streaming server. It will also require your end-user to download an activex component. it works really well though.
unfortuanately, this is not a cut and dry operation.
I haven't used the software in a while, so i would recommend reading the installation instructions and the FAQ's before you install anything to make sure you really want to use their product. I think you also need to have IIS running, but i don't think its required.