Flash video issues, youtube issues

I’ll look to see if there is a tutorial for this, but my question is:

How do you integrate a Flash website with a video on your server OR a video that is externally linked on youtube?

The idea is to create something where any video file can be played seamlessly on the same page without having to go to an actual youtube page. Wordpress has done this, because when I typed in the address of a youtube vid in one of my posts, the actual video was embedded.

JTV also does this. However both sites are made with HTML/PHP. My current homepage is Flash.

Thanks for your advice!