Just make small script to do conversion from Garmin GPS data or maybe other GPS with (East/West & North/East) Degre and minute value format into latitude and longitude format that usually I used with google map.

Example Garmin Waypoint Data :

Waypoint    NodeName        User Waypoint    S7 28.180 E110 56.250

It will South (S) 7 degree and 28.180 minute  , East (E) 110 degree and 56.250 minute

Check this address :

http://a3-system.info/demo/longlat