Camscott has created his take on some of the characters and how they would probably look like if they appeared in reality, based on the characters' origins in The Railway Series. I believe there's only Thomas, Edward, and Henry, with no intentions to create any more in the series. Each comes in four forms.
Henry comes in his original form, with a GNR style cab, since it is said that Henry's original design came from rejected plans stolen from Doncaster. He comes in green, blue, and in face and faceless versions for both.
Edward comes in as-built form (cut-out cab and different wheel arches), in what is speculated to be how he arrived on Sodor, as well as rebuilt form (windowed cab with flush wheel arches). Both have face and faceless versions.
Thomas comes in as-built (forward slope to his footplate below his smokebox), and rebuilt (straight footplate). Face and faceless versions, too.
On top of that, there's also Annie and Clarabel models, both face and faceless, based on the original models the Rev. W. Awdry made.
Camscott's models used to be available on The Sudrian Community site, which has since shut down.
You can find them here now:
http://si3d.proboards.com/thread/3040/camscotts-models?page=24
Though, you'll need to register on that site in order to access it. Camscott is known to be a brilliant creator of British models, mostly payware. His Thomas models are one of the few freeware models he's made over the years.
Here's a comparison of an older model of SI3D's Edward and Camscott's rebuilt Edward:
An artist's altered screenshot of Camscott's faceless version of rebuilt Thomas, Annie, and Clarabel, with Edward in the background. Rather than Thomas being modeled as his real-life basis, an LBSCR E2, he's modeled after how he appeared in The Railway Series.