Yes this should work fine. You would need to update google maps to the latest version, which you can do through the android market at home (connected to your home wifi). Then you can also browse the google maps at home and cache the locations you need when you are out and about. You do not need to use a pc at all.
There is actually 2 types of caching happening. One is an automatic cache of whatever areas you view most recently. The other is in the "labs" setting I am referring to where you can explicitly tell google maps which areas you want to maintain a constant cache for.
But be aware that caching doesnt seem to have the same level of detail, eg 3d buildings, that an active inteenet connection provides.
Sent from my LT15i using GeoClicks Mobile