Interesting topic. In my experience, if you really want to learn how to put together a YouTube style site, or any other "step up" style site... Learn all the pieces by hand coding. No dreamweaver, no frontpage, no wysiwig, and no adobe flash servers. You dont need them. Everything you need is on the Internet for free. You only need a machine or VM.

Heres my YouTube Laundry List:

Server (dual procs 4 gig ram)
PHP
MYSQL
Apache or Lighttpd
FFmpeg (key ingredient)
GD Library or ImageMagick
LAME MP3 Encoder
Maybe some other goodies

Learn root access linux admin stuff... just the basics.

Once you can set that up in a Linux enviro... program up some stew... then you'll be on to something if you really want to make it yourself. I find that it really helps create unique ideas for web development going the loooooong road.

Take the linux road less traveled. - some dood