Yes, www.garmin.com/express is an official website for here you can update your software for free. But, first, you need to follow the simple step, and you will be able to download the software.
Step 1: You can connect your Garmin GPS to your computer using the USB cable that you get with the device.
Step 2: Open the browser and visit www.garmin.com/express Garmin's to Find Map Updates page.
Step 3: Select "Automotive" and click "Download Map Updater." Save the file to your desktop.
Garmin GPS update,