I did a few weeks ago, a simple phone call to the Valuation Office Agency. I suspected we were wrongly banded for a long time - our house was built in 1999 and has 3 beds and small garden; it is one of 5 new builds, and the rest have 4 beds and large gardens. From the outside they all look the same, and I suspected that they were all blanketed together (by a lazy surveyor) when they were banded
Got a letter today saying that were had been in Band E and should be (and now are) in Band D. The difference in our Local Authority is £300/yr. We have been inadvertently overpaying for 8 years and 2 months ! I understand that the LA has to pay this back to us!
If you have any reason to suspect you are paying too much council tax, ring the Valuation Office Agency, tell them why and they'll look into it for you. All free, and very easy.
Info here