Setting up collision for THIS

http://archon2160.pbwiki.com/Public%20Showcase

If you check the screens you'll see my first project ever in Blitz3D. Now Im working with collisions and am wondering how I can solve this problem:

I want things to bounce back when colliding at walls. The walls have different angles so the bouncing back must be calculated diferently.

How do I do this without involving hardcore physicengines? Suggestions?

If the wall mesh has normals, you could maybe read CollisionNX, CollisionNY, CollisionNZ after a collision, and use them as the new direction of the vehicle.

Oooh just what Ive been looking for.. Thank you thank you!
As you see Im a newbie on this one (Im an artist normally)

have a look at this: http://www.blitzcoder.com/cgi-bin/code/code_showentry.pl?id=darkeagle04082003132045&comments=no it'll probably give you a hint in the right direction :)