Random numbers and item purchasing

First off, is there a way to make a random number? I figure there is via Jass, but does anyone know how to do it.

Second, how do you get a computer controlled hero to purchase an item? I'm writing some AI for botg and can't seem to find this one. I can manually give them items, but I want them to purchase them. Anyone know how to do this?

Thanks in advance.

In GUI triggers there is a Math - Random Number for real and integer calls

And to make a hero purchase an item in a shop you'll need jass:

http://www.wc3campaigns.com/showthread.php?t=31264