there's a pretty active group here: http://groups.yahoo.com/group/NA_16mm_SM/
Their trains run on 32 mm (O) track in 16mm scale
MTH and Lionel make 2 rail scale trains (not toy) that use DCS, DCC or TMCC (alphabet soup) and 1:48 scale on 32mm track
The Home of Articulated Ugliness
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