Should have looked into this a bit more before I bought it but anyway.
I’ve got a Samsung Galaxy 50 mp3 player which has a gps builtin. It came with Google maps and Navigation loaded on it. But I didn’t realise that the maps are all web based. So if I’m out somewhere I don’t think I can simply use the device to navigate somewhere else. I have to find an internet connection first so that Google can download to the device’s cache the maps that are used along the route I want to take. Am I missing something here? Can I download Google maps and store them on the device? If not, are there any other mapping/navigation systems I can download (from the android market ?) that means I have maps permanently available on the device?

Google maps is completely web based, and will always be…
I’d suggest trying something OpenStreetMap based, that allows you to download and cache the maps
Check out MapDroyd
http://www.mapdroyd.com/

Have a look for NavFree. They do an app for the iPhone and I think there ‘may’ be one for Android soon if not now.
All OpenStreetMap based and you download the maps to your device so they work anywhere. Free.
Bleedin fantastic.

Or you could just get your wife to actually ask someone for directions…