In case you've been itching to create nifty stuff using Google Maps (such as this cheap gas hack or this IP traceroute hack), you should check out this very nice Google Maps API Basic Tutorial. It walks you through all the basics of bending Google Maps to your twisted will through a series of 12 exercises covering both conventional and object-oriented programming. If you're getting really ambitious, you might also want to check out myGmaps, a site that lets you create and host your own custom Google Maps datasets.