There are many PLC suppliers on the market, e.g. Siemens, ABB, Allan Bradley (Rockwell Automation), Honeywell, Toshiba etc. etc.
These PLC's all have to be programmed by the user for the desired application. You have a choice of different PLC languages e.g. Ladder, Structure code, Function Blocks and Sequential function chart.
Now, some companies do have simulators (e.g. ABB and it's AC800xA range with the AC800M PLC controller), but that's usually intended for the end user who actually bought the full package, (and were not talking about peanuts here
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There are small PLC units available on the market that mainly uses Ladder logic as programming language for the average light usage user. As was mentioned earlier, visit some of the PLC forums on the net. (Search for PLC with Google).
I'm sorry to say that what you’re looking for is not going to be so easily available as most training and simulation packages are for the Microchip range of equipment (C, ASM and basic compilers to name a few)