The official manufacturers of these devices don't offer downloads related to drivers, user guides and anything a common user might use. Therefore, the only way to obtain them is through the direct contact with them. However, before doing that, connect the device to your PC and connect to the Internet.
Once connected, start Windows Update and check your computer for updates. There is a very big chance the driver will be installed this way.
Contact them locally using the dealer locator function available their website: http://www.wepindia.com/Gmap/default.aspx?PAGE=CONTACT