depends on your budget. Plenty on the market with GPS that you can do nice google maps overlays onto.

YOu can get some good chinese tat off ebay but with all the chinese stuff you have to do your research to ensure you are ordering a good product.

If you want warranty and all that then theres loads to choose from eg roadhawk, Nextbase, Blackvue, Mi, to name just a few of the main brands.