Here's a list of some of the weapons I personally encountered from time to time in afg:
Rifles:
AK, of every version from every country that ever made them
the occasional SKS and Mosin
Various Enfields and Mausers
Pakistani G3
A US M1 Garand in serviceable condition was recovered from a cache, with no ammo
A VZ58
2 M82 Barretts of early design were recovered from a cache in Kandahar province in 2006 by our task force. No optics mounted. Would love to hear the story behind them.
Sometimes antiques like Martini and Snyder rifles were found hidden away- never shot at by one, AFAIK.
As of late, various versions of the M16 have been recovered from enemy forces, due to our practice of arming the "good guys" over there. The stuff always ends up somewhere else.
MG's:
PKM
RPD
SGM
DP
SGM
DSHK
Found a magazine for a BREN 303, but not the gun
SMGs:
PPSH41
STEN
Handguns
Tok TT33's
Makarovs
Webley and Enfield break top revolvers
S&W 9mm sigma- bought in large numbers to outfit the afg police, recovered in large numbers from the enemy "after".
Serviceable sidearms were normally gifted to our interpreters, who were usually only issued an AK.
Things that go BOOM:
RPG
Mortars
107mm rockets triggered by hot-wire delays
Mines and IED's made from arty shells, fertilizer, and anything else they think could be made to explode.
Other:
random single and double shotguns made by Baikal, sometimes sawn off.