Local History Societies are worth checking out, too. I found that one society where some ancestors lived had transcribed and made available online on their website not only all the parish registers for the parish but also the censuses and the school registers and a vast range of personal memories by older residents - enormously helpful and the latter really brought the place to life for me.
So now when I am looking at an unfamiliar area I always check to see whether there is an active local history society, they are usually keen to be helpful.