Garmin POI Loader

You can download "POI Loader" from the Garmin site.

Then you can create simple CSV text files containing points in the right format, and load them into a Garmin handheld with POI loader.

Here is the format of the file, cribbed from Garmin's docs

<Lon>,<Lat>,["]<Name>[@<Alert Speed>]["],["] [comment]["]

Longitude and latitude must appear in WGS84 decimal degrees format (ddd.ddddd; negative numbers indicate West and South).

If you include quotes around the name or comment, you can include line breaks in the text. The following are examples of Custom POIs in the proper format:

-94.81549,38.80390,Bonita
-94.79731,38.81099,Ridgeview@25
-94.74240,38.81952,Heritage Park,Perfect site for a picnic
-94.76416,38.81227,Garmin,"1200 E. 151st Street
Olathe,KS 66062
913/397.8300"

Download POI loader and refer to its internal docs for more information.