Thank You both for your reply and the info.  I keep looking and learning a little more at a time. 
I think it looks a little more expensive than what I have to play with at the moment, so I have time to
try and learn a little more. 
  I actually went the thefavoritespot wearhouse.  Wow they have a lot of stuff. and Super Nice Folks.
The owner was not there the day that I went. But one of his crew gave me a Bachmann train catalog.
And let me look around.  Like I said Super nice folks.  I will for sure go back. 

So another question. what brand do you guys like best as far as the aftermarket sound systems or boards?
I guess that most of the boards and speakers and such are made to fit certain engines or makes, like a
Bachmann Union Pacific dd140 or a different engine?  I guess I need to figure out what engines I have that I could add the stuff to
or just get one already to go first.
  I will find out more about the controllers and etc...

Thanks Again
Patrick

 Hi, I have been collecting HO trains for a long time, but I just noticed the DCC and Sound engines.  Really Cool.
My question is this.   
For someone that has only old style trains.  What do I need to get to run sound? What do I need to run DCC.  I kinda understand that I have to get a DCC controller and that the DCC powers the track all the time and the DCC tells the engine what to do. But what do I need.     There are so many different systems that I have seen so far and I am just slightly confused.
   Is it a separate controller for sound?   or what? 
If I bought a Bachmann engine that says DCC on board. will it work with my old system?   
  Can you have a engine with sound with out DCC?
I have been trying to research some of this on line with not a lot of luck.  I went to my local Hobby store Hobby Town USA. The person that was to be the one to talk to about Trains, was a snotty twerp.  said well we don't keep those trains in stock cause they are to expensive but I can order you what ever you want.  I looked at him and said well that's the thing, I am new at this and not sure what I want or what I need.  I just got a blank stare in return.
So I figured that I would ask here and see what gives.

   Can you add DCC & sound to an older engine? 

I guess I just have to many questions.

Please Help Thanks
patrick