When searching for a city on google maps, google is that smart it displays a geometry line on the boundary off the municipal. See this link: http://g.co/maps/23dz5
Is there a place in the google maps api where I can download this geometry?
actually you are searching city boundries of world. and you can get it anywhere when you find free data...there is lots of option but which country are you interested in?
For free shape file you can use :
or if you want whole world :
The coordinate reference system is latitude/longitude and theWGS84 datum.
And dont forget:
These data are freely available for academic and other non-commercial use. Redistribution, or commercial use, is not allowed without prior permission.
i hope it helps you...
Simply put: no, there isn't. If you need the data but don't want to invest lots of money, you could use the data provided by OpenStreetMap. I have found it to be reasonably accurate at least throughout Europe.