Non-DCC sound for a railcar?

[Texas Zepher]

I don't know how simple they are but Phoenix Sound come with several different gasoline sounds.

http://www.phoenixsound.com/library/other.html

[Stevert]

I have no experience with Ram Track, but they have some sound modules so you might want to give them a try. 

http://www.ramrcandramtrack.com/

[Ray Dunakin]

Does anyone make a simple, non-DCC sound system to produce sounds for a railcar? It doesn't have to be specific prototype, just a basic gasoline motor sound would be fine.