You need to use some JavaScript stuff to show your map. OpenLayers is the number one choice for this.
There is an example at http://wiki.openstreetmap.org/wiki/OpenLayers_Simple_Example and something more advanced at
http://wiki.openstreetmap.org/wiki/OpenLayers_Marker
and
http://wiki.openstreetmap.org/wiki/Openlayers_POI_layer_example