The Train Dispatcher 2 is available for free through the link posted below. This is only way to obtain the application. If you will need version 3, then Ebay needs to be used because that's the only place where the product is sold.
Access the following link to download the software for free, as stated by the developers: http://www.signalcc.com/train2/td2freeware.html
Secondly, if you have a newer version of Windows, then remember it won't work. You will need Windows 7 or Windows XP emulated through a virtual machine.