The asGPS plugin allows geotagging with Google maps support inside ASP. It shows a road map or satellite view with several options and addons:
Images which have GPS information are marked in the map. You can search nearest location for them. Images without GPS information can get it by clicking in the map, searching nearest locations and push all theses infos into the IPTC fields of the image. Locate images in the map by searching their IPTC info within Google maps. Auto search/locate and tag modes available by ctrl-click on the buttons. This mode allows automatic searching or locating in the map on every hotness change. Moving the marker with shift pressed tags the image at once.
All tagging fields have tristate check boxes which can be set to enabled, disabled or overwrite only if empty. Use the optional external map window for a larger view outside the ASP tools box. Track files in GPX and CSV format are supported, visible in the map and can be used to locate images by matching their time stamp with the GPS time. Holiday support with weather, traffic, bicycle path info.
It is free with open source code and a PayPal donation button on the help page.
Download from here: http://aftershotpro.com/plugins/index.html?plug=asgps
Thanks to Keresztes Barna (kbarni) for providing code for reading and using the GPX and CSV track files!!