Is it possible for a homeowner to apply that stone veneer stuff over existing stucco with a high level of success? Any advise on which stone stuff to use? I've seen a couple of actual stone options at home depot. I'm afraid to attempt it. Will the exterioe of my house be ruined if it doesn't work?

Stone veneer 'stuff'?

Can you be a little more specific, perhaps a link to the product your mentioning?

Stone veneer or faux stone can be applied to almost any solid exterior. To do the job right the stucco should be removed so you can attach a new metal screen mesh which is the base for the first coat of mortar. Have you ever done any brick or block installs before? It is not hard, maybe a 6 on a 10 point but you can screw it up if you don't know much about masonary work. How to Install Cultured Stone Yourself | eHow.com