Origins of the music used in Portal's teaser trailer?

[Bruner]

So I found one of those songs used in Portal's teaser trailer, called "Barwy Gitary" by LeBlue:

Does anybody else know what the other three songs that play at 0:00 1:01 1:14 during the trailer are called?
I'd especially like to know the one during the introduction.
Any information about them would be great!!

[Bruner]

Bumping this up. Again, if anybody knows any of the music used in Portal's teaser trailer, that would be terrific.
(Aside from music from Portal and HL2 ost)