Garmin GPS coordinates?

I got some coordinates from google earth that I wanted to try and fish, but when I manually put coordinates in gps they seemed to be off, some was even showing on land, could it be I have wrong setting on gps? I know there are a couple of different types of coordinates used, anyone know what I should have my settings on gps set for to match google earth?
Thanks for the help

You will have to have them formated to fit your garmin , find out what format you need and then you can go online and convert it to your garmin format and then put it in your unit manually or with a sd card if it uses one.

Google Earth files are .klm files. You will have to convert them to .gpx files.
gpsbable is what I use.

one of two ways, I have done both lately.

1) Garmin's waypoint coordinates when manually entering are 99.999999 or similar, there are no online conversion tools using this format I could find, so i had to manually figure the minutes etc and convert them to the Garmin format.

2) Simply save My Places with your waypoints (tracks work too) in Google Earth in the KML/KMZ format, then use gpsvisualizer.com to convert that to GPX.

Waypoints work perfect, Garmin is really bad about wanting to connect track segment ends though.

You can also download Ride Leader by Trail Tech(it's free). It will open gpx and Google Earth(kml) files. Save your Google Earth file as a kml and NOT kmz file. Open this file with Ride Leader then just save it in gpx format. When you open the file with Ride Leader you can see your points and trails in Google Earth within the Ride Leader software. Ride Leader works with track segments too.

Thanks guys I think I got it, once you convert it is it pretty accurate, what I am marking is stumps and brush so not really big targets?