GPS Maps

Having bought my Garmin GPS recently I now have needed to locate some maps to upload into it to make life more interesting (my street is a blank space on the basemap that is supplied with the GPS). Given the relatively high cost of Garmin MapSource products (£129), I started to trawl the Internet and asked in a forums for advice and alternatives:

UK CAA Airspace overlays
http://ukgarminairmap.wikispaces.com/

Free Garmin Maps
http://garminmapsearch.com/

I haven't tried any of these yet (my new PC doesn't have a serial port and so I have had to order a card - still waiting!). Will post an update when I get a Map into the GPS.