John, welcome to the site. I use
Tracks-n-Troops out of Belgium for most of my 1/72 scale armor details. Great service and good prices. Also,
Eduard makes several detail sets for 1/72 scale armor. They are available through most online vendors in the US.
If you surf Tracks-n-Troops' site, you will see several manufacturers that make 1/72 scale photoetch weapons sets. Check out ExtraTech's photoetched 1/72 scale WW2 German, US and Soviet weapon sets.