Has anyone here used this site to get their estimate of your home’s market value?
If so, how accruate did it seem?
Finally, did it result in a flood of unwanted emails from real estate agents and others?

I’ve never tried it for exactly the reason that it requires registration, but the estimate from zillow is pretty close to what I figure my place is worth. Their accuracy varies depending on the amount of info available on-line in each state; here in Maryland there is a wealth of such data, including home sale prices, assesments, and the like.