Can't remember last time I uploaded an image. Since discovered that photo bucket and instant image no longer allow uploads to a forum for free subscribers.
Imgur it's free but like all photo hosting website it can disapear or being payware so in cas of that: upload your pics and save them on a file on your computer
You might also consider creating your own web site. There are loads of free site creators out there including Wordpress and others. Once you have a site, you can use it to host your pictures and KNOW where they are and how secure they may be. I use my own site all the time to host pictures. Mine is rather extenseive, but only costs me around $85 a year.
Mosey over to where your T:ANE data lives and go to the Screenshots folder. To get the exact path it's easier to do this:
Open up T:ANE Launcher.
Go to Trainz Settings
Click on the install path.
This will show you were it's located, which by default is that gawd awful C:/Users/(your login)/App Data/Local/N3V Games/TANE/Build something.
The something equals a bunch of letters and numbers.
(When I reinstalled T:ANE back in the beginning, the first thing I did was put the data on another hard drive under a TANE_DATA folder. It's a lot simpler and saner to find).