Gps tracking with voice navigation

hi
i want to do GPS navigation with voice announcement in outside, I panned to do with aruduino board i want to buy GPS for high accuracy purpose which model is best ? and how to do voice announcement like as Gmaps , Example I fixed 3 locations i move to that any of 3 fixed location the voice announcement want to come , how to do this concept please suggest me. any option available download the location with voice from Gmaps?

Thanks