Alright I think this is the right place, I need some help as I am stuck writing a classical piece of music. I play in a metal band but i am very fond of classical music and have incorparated some classical sounding riffs in my songs(i am no classical guitarist, I don't know theory or anything but I can play alot of classical pieces with my own techniques) and I wanted to write an intro track for my band's cd. Something in this style: http://www.youtube.com/watch?v=H5p1brK7pH4

I know its wasn't written by a classical guitarist but still that kind of thing. Anyway can anyone give me any ideas on what kind of chords to use or progressions, should I vary time signatures etc...

Any help wwould be much aprreciated.
Meh, I dunno. Tbh, the music in that video lacked the structure a piece of classical music does but as a few pointers, you are going to have to learn theory and lots of it. To write some music for guitar theory can be over looked but for writing classical guitar you have to think about harmonies, scales, cadences. Going in there without theory is going to be very very hard mate.
Yeah, writing classical music without knowing your theory is more impossible than *insert clever analogy*.
^ That's really not that hard...

You get used to it after the first couple of times.

How about:

Writing classical music without knowing your theory is harder than the boners of Pit monkeys in the Hot Chics thread.

Erm...that failed too, methinks. =[