I'll leave off livestream for the moment and all the new file types in live streaming for a noob.

If I wanted to capture audio from youtube-- LP recordings for example-- which
software can do that? Line In which I would normally use works from my
audio receiver. Trying with Audacity for example, I had no success i getting a capture
from a net source within the browser streaming youtube.

Is there any special hardware needed for livestream capture: huge HDs, high end vid cards
and so on? In the stickied thread that seemed to be indicated.