Finding media urls

[Kport]

I want to find the full urls of media files that are hosted on sites like youku,megavideo etc..

I want links like: http://www.megavideo.com/v/QJQN21EX6...700f36291f6f5d (http://www.megavideo.com/v/QJQN21EX6441ef8b6839f06095700f36291f6f5d)

instead of http://www.megavideo.com/?v=67AX20PO

any idea how you find this out?