Procedural 2d landscape generator

Hi,

Anyone know tell me how to start with the development of this script?, I would like the end result would be something like:

Thx a lot guys.

Here you go: http://www.youtube.com/watch?v=nPX8dw283X4

Ey jeff!! thx!! but…

I need a complete tutorial, this is pretty good but does not show all that is needed.

And I think I need not implement something as complex, just as I show in the link.

thanks