Here you go! (blog is not mine)
http://densha-de-go.blogspot.it/
The list of versions avaible is:
-Final (it's the only one that needs the "crack")
-Ryojohen
-Sanyo Shinkansen
-Professional 2
-3 Tsukin-Hen
-Nagoya Railroad (wich i recommend for beginners)
- Professional
-Densha De Go! 2
-Kisha De Go!
-The first version ever
Instructions:
Download the files from MEGA, click on the exe; a window in polish will open, then click on "Wypakuj" or something like that, wait until it's done, it should leave a folder with the cover of the game and a .ISO file, open it wih DaemonTools or VirtualCloneDrive, then the installer will appear.