Free Electoral roll Search
192 offer free and premuim searches
Before you consider paying for electoral roll searches remember that there are lots of free results available. Whilst there is no guarantee that the person you are looking for will be found within the free results there is a good chance they will be, or you should at least be able to get some historical data on them.
Even if no free search results are available then the premuim results don't coct much to access, usually a few pence each, and before you buy credits you will be able to see some limited information from these paid for results, like the persons middle name and area where they live, meaning you are not taking a shot in the dark.
An example search page is shown below, with the free results at the top and premuim results below. Click on the image to enlarge.