Step by step how to get UUID

Hello everyone,

I'm using Vmwareplayer 5 on a win7 64-bit machine. Could someone now explain in detail (step-by-step would be the best since i'm a real newbie on this) how to:

1. Gather the UUID Number from an existing VM
2. how can i change this number to a number of an existing vm.

Or in other words: I want to create a NEW vm of my my computer, but it should get the UUID of an Old Vm i used months ago.

Thx!