If its in good shape (no rust) expect $1/piece on eBay for used track, more if you're lucky. NOW is the best time to sell it. After the holidays expect that price to drop.

-Brian

One of our club members owns one and it has been passed around a bit. I have heard it works great.

-Brian

If something does happen to it, hopefully it will be within the warranty period. Then you can send it into Bachmann and maybe they will send you back a version 5.

-Brian

http://www.girr.org/girr/tips/tips1/big_hauler_tips.html#gears

Its not appropriate to ask where to buy non Bachmann products here. There are plenty of other fora to do that like - MLS, LSC, LSOL, and GR.

-Brian

Your Silverton Express is a Big Hauler Set in 1:22.5 scale, just a bit larger than 1:24. A five foot person would be just over 2.5 inches, 6 foot person, a bit bigger than 3 inches. LGB and Bachmann figures are 1:22.5.
There a quite a few commercially available kits than can serve as guide line. Piko and Pola kits in 1:22.5. Colorado Model Structures (http://coloradomodel.com/) and Smith Pond Junction (http://spjrr.com/masterkits.html) in 1:24 and many more. Grandt Line makes windows and doors in 1:24 also.
Some on line resources for railroad structure dimensions - http://www.cwrr.com/Drawings/ and http://prr.railfan.net/standards/standards.cgi?plan=&rr=&type=STRU.
This http://www.grblogs.com/index.php?blog=25&cat=82 will take you to my blog showing my kit, kitbashed and scratch buildings.

-Brian

Yes that's them. There's a diagram inside on how to install them.\

-Brian

Brennan (Bones) and Booth are investigating the death of Kris Kringle tonight. As they enter the dead man's apartment and flip on the lights, it activates a Bachmann big hauler train running around a chest high suspended layout.

-Brian

http://www.girr.org/girr/tips/tips1/big_hauler_tips.html#gears

Okay Vic  . Lots of critters and switchers to model but narrow gauge road engine prototypes are pretty scarce  .

-Brian

Current value of the dollar, the 3 axle trucks and smoke unit were already designed, and inflation would put that amount over a million for a complete ground up design  these days. I don't know who is buying Mike's large scale locos. Out of the hundreds of locos I have seen in person only one has been MTH outside of a boxed one at a train show and I live 20 mins. from their headquarters. I suspect heavy subsidization from their O scale stuff but that's a discussion for another forum.

-Brian

The smaller scales, HO, N and O, are much larger markets than large scale. In smaller scales multiple manufacturers can make the same engine and still make a profit. The expense of making molds for a new engine is huge (over a million bucks) so there has to be enough of a market to justify that expense. Aristo and USA both make a quality product. You often hear whining over on the boards about wanting this or that  loco but without the ability to sell many thousands of the loco the manufacturers can't make money doing it. Hence the demise of LGB, MDC in large scale, Kalamazoo, and Delton.

-Brian

As Paul said, there are not many narrow gauge diesel prototypes around. LGB offered a Yukon and White Pass model. Besides that model, there would be only a few D&RGW switchers, the Plymouth switcher, South American exports and Euro prototypes to model.

-Brian

Welcome Chris!

1) As above, I have never seen them sold separately except on eBay. Another option to to buy cheap cars and repaint them green or red (spray paint works fine) and decorate them yourself. I have down this with a few cars.

2) Yes, with a couple of caveats. Different manufacturers use different knuckle couplers (their own). Most can be manually couple together by hand. Your other alternative is to use the hook and loop type couplers. Most manufacturers provide them also.  Your train is 1:22.5 scale. Large scale trains run 1:20 to 1:32 scale for the most part. Trains in the scale range of 1:22.5 to 1:29 look okay together to my eye. This includes the Bachmann big hauler line, LGB, USA Trains, AristoCraft and Hartland.

3) Yes, your ten wheeler should be about to handle 6 cars on level track.
It could handle more on a larger diameter track. The track in you set is the minimum 4 foot diameter.

-Brian

Yes, eBay is the only place you will find the large scale Lionel Thomas trains and they are usually pretty pricey.

-Brian