The Mother Lode

They are not knock offs. They look like from Toy R Us' Imagariam (Sorry I can't spell) battery train line (first generation).

Edit: I found some images 

<img src="http://trusca.imageg.net/graphics/product_images/pTRUCA1-19339947dt.jpg">

<img src="http://img.photobucket.com/albums/v137/cupcrazy/a_1.jpg">

I did a small review on this set

http://publictransit.byethost33.com/toys...%20Set.htm

The engine is too tall to clear Tomy tunnels plus easy to break.