EXTREME NEWBIE NEEDS HELP

[castcreator]

Hi everyone. I am really new to the whole gps thing and even newer to the gps file thing. I got a couple of questions, maybe someone could help? I downloaded the newest base camp and cannot get any of these topos or any map to load on it. I live in indiana, so I downloaded the indiana topo stuff. Basecamp will not recognize any of the formats. I downloaded the my trails installer off this web page and installed it. All that there are are .img files. Nothing that mapsource or basecamp will utilize. I walked thorugh the tutorials. Nothing seems to match what is downloadable.  By the way, I have a Garmin NUvi 1450lmt, windows 7 operating system.
Let me ask this, should i be able to see everything in basecamp and mapsource thyat i will be able to view on my garmin???

[Seldom]

Have you read this?  http://www.gpsfiledepot.com/tutorials/how-to-open-maps-in-garmin-basecamp/

Keep in mind that once the installer has been run, they are already in BaseCamp you select them (see second graphic in the tutorial).  File|Import doesn't load maps.  It imports your tracklogs and waypoints.