Run webupdater and you can download all that you need.
If you have totaly empty nuvi, create new folder and add name Garmin, turn off and then ON nuvi and you will have garmindevice.xml inside and now run webupdater.

If garmindevice.xml don't create, then use prepusb tool to format nuvi and then create folder Garmin and you will have garmindevice.xml inside when you turn off/on nuvi.