XNA randomized tile/terrain generation tutorials?

I've been trying to find a good tutorial on how to program randomized tile generation (2D). However it seems that i cannot find any proper tutorials on that.

Is there any books and/or websites with proper tutorials on how to program it and the math behind it?

I know this is not a programming question per se however it is programming related, so hopefully someone can help me out with a link or two.

Solution

A good introduction to random terrains
Very basic 2D terrain tutorial
And .this one i found a little more confusing, but it has a lot of example code.

But remember if you use other people's code give them credit :) hope these help.