Amazon is currently offering Thomas and Friends DVDs with bonus pack wooden train included for $7.49 each. Usually just the wooden trains cost around $10 each. These are the DVDs available:
Thomas & Friends:James Learns A Lesson w/ double train
The Thomas & Friends: Best of Thomas with one train
Thomas & Friends: Thomas’ Trackside Tunes with one train
Thomas and Friends - Tales From the Tracks with one train
Thomas and Friends - Songs from the Station with one train
Shipping is free if you purchase more than $25 in one order. If you have a Thomas lover you could start or complete a train collection with this offer. As the trains offered are different for each video it seems.