I have a Shadow and am learning all kinds of things that make me love it more and more. it is a GREAT lower priced phone to get you into the smartphone (mobile pC) category.
I have a Yahoo Goup started where I post alot of tips and tricks - check it out to learn about it.
shadowphone : The Shadow HTC Phone by T-Mobile
Or try youtube - there are lots of cool vids about the shadow. search "t-mobile or HTC shadow".
I am sure your cousin will love it. It's a great phone and the new NEO interface developed by Microsoft and T-Mobile together is like nothing else out there, it is REALLY sweet.