On James Island, there is a strip of Camp Rd., just down from James Island Middle School, where a bunch of families extravagantly decorate their front yards and homes. Bayview Farms Subdivision also usually has many decorated homes....St. Johns Woods is very pretty and several other subdivisions here on Johns Island, but can't think of the name of them. We drove around after Christmas Eve service last night and saw many pretty ones, but I also noticed that some people who normally decorate did not this year....maybe due to the economy? I know that I am the only house on my (country) road that is decorated this year when there are usually 4 or 5 others who also do.
I would just drive around through every subdivision you get to and I'm sure you will see decorated houses. There are some in West Ashley and Summerville where I've heard the neighborhhod goes all out, but I don't know where they are.