GPS has made life a lot simpler. Instead of buying maps before every trip, you can get Garmin Maps on your GPS from the Internet and save yourself the expense. Garmin map is the answer for all those who are tired of navigating through the commercial maps. PSmapsearch.com, Maps-GPS-info.com, Map Center 2, are some of the sources to get free maps. OpenStreetMap is the map encyclopedia that is Garmin compatible. It has pre-compiled maps that you can get on your Garmin GPD for free. In any case, you will need a Garmin GPS to which maps could be added.
Select the map you want to download. There are many websites that offer free maps. OpenStreetMap is like a map wikipedia, Cloudmade includes map from all over the world and My Own updates the maps from UK and Eire weekly.
Browse through these websites and choose from different regions and download the map. Once you have downloaded the map, unzip the .IMG extension file.
Take off the battery compartment of the GPS. In order to load your map onto the SD card of the GPS, push the silver card on left side of the batteries and it will come out. Load the SD card into the card reader.
If you have a USB cable, connect your GPS using that. Go to Garmin.com and get the Garmin drivers. Install them on your system. Select the Setup Menu from Menu Screen, and choose Interface. Click on USB Mass Storage and your GPS would become a USB device.
Select the existing map on your SD card and copy it to your PC so that you don't misplace your old map. Once you have pasted the old map in a folder, delete it from the SD card.
Copy the map you downloaded to the GPS's Garmin folder and rename it to GMAPSUPP.IMG.
Remove the GPS/insert the SD card back in your GPS and restart it. Your map will appear in your GPS.
Check the sites for updates and install them at least once a year.