Bradley,
If I'm looking for something I'll generally start out with google and see if I can find it on google image search if it's not on the DLS. I've found a lot of stuff that way but you have to be prepared to translate some of the pages unless you're good at interpreting/guessing other languages.
If you search "Flexity Tram Trainz" in google images quite a few results come up. The only thing I'll advise you though, is if you're taking assets from a third party website, sometimes the dependencies aren't always in with the content so you then have to spend ages on a cross between google, thekuidindex and various Russian forums finding what you need. Also note, that sometimes they also tend to come across as faulty (I had to delete a tonne of attractive Polish & Czech trams because of this) as I couldn't fix them.
I hope this helps in your search.
