There are 2 toy stores with a large selection of games near the Rathaus in Salzburg. One is called NeuMuller, which is in Rathausplatz. The other is Klexx and it is across from the Markt bridge on the old town side, across from the large grocery store Bille something.
Just been there today, can't find neumuller, also the webpage is gone, so likely they closed already. Klexx is quite a big toy store in such a compact town, with quite a good selection from kosmos and ravensburger.