You can install QGIS 1.8.0, and the Openlayers plugin which serves you with an Openstreetmap background.
You can import your data as text delimited layer, or GPX points layer, and print them on top of the Openstreetmap background.
If your data is in lat/long degrees, the Coordinate system for your layer should be
EPSG:4326 WGS 84. The project CRS has to be
EPSG:3857 Google Mercator. With "On-the-fly-projection" activated in
Settings->Project Settings, both layers should align.
The open-source software viking http://sourceforge.net/projects/viking/ does a similar job, maybe easier for a newbie. QLandkarte GT http://www.qlandkarte.org/ is similar to it.