Is it poss to get new voices for this device?

Yes it is. Though perhaps the ones on the Garmin site are a bit, shall we say, an acquired taste. Talking Squirrel anyone?

http://www8.garmin.com/vehicles/voices/

There are third party sites doing voices but they will cost you, typically a fiver or so per voice. For example

http://nav-voices.co.uk/Scripts/prod...?idCategory=73

There's also a tool available for free from Garmin to record your own, if you're the creative type.