It sounds to me that you are not doing quite the right thing. Assuming you want to use mapsoursce. You should have downloaded the mapsourcse version after doing this and extracting you should have a directory similar to

sorry wrong button - City Navigator Middle East NT 2011.10.gmap This is a "Folder" inside will be 4 or 5 other files 1 ending in .mdr and another ending .mdx . You place the entire folder into - C:\Users\anwar\AppData\Roaming\GARMIN\Maps and then restart Mapsource it will appear in the list of available maps. gmapsupp is a file that would be used on your garmin device.