You can download a Military Grid Reference System converter from here: MGRS Converter
It will give you coordinates that can be entered into any map program, such as, google maps. You can also download Google Earth, it will automatically locate MGRS coordinates if you append the coordinates with mgrs.
Afghanistan is the AO, so short of looking up specific coordinates related to specific events I'm not to sure how else you could get specific maps.
EDIT: I have a high definition map of the Qalat Area in the Afghanistan AO, I don't have any grid references or placenames on it at the moment but it certainly depicts the area well: Qalat Area