HI @puddlerocks
Have you looked at the Tutorial section of the forum yet? There is a lot of good information there.
I would think that you will need some high-current switching electronics or a relay as @peekay123 mentioned in his reply. Then you will need to write a sketch that has a Spark.function() that allows you to control your motor.
There are lots of ways to do the web side of this, but here is a simple way to get started. This example uses a tiny servo, but can adapt the same idea to a DC motor.