Over on Thinking in Seam, I've been running a series on working with Google Maps using Seam and I thought it would be an idea to put the links to the series in order on here.
First part of the process is to add a tag onto the map using the GMap tag from the RichFaces tag library. This processed is described on Markers in Google Maps.
Secondly, a little note on UK postcodes with Google Maps (in that, due to licensing issues, they do not work).
Next up is how to populate your Google Map - be warned, it's a big article! Also, there's the follow-up article in which a couple of issues I discovered after posting the original article are addressed.