John Titford, editor of The Penguin Dictionary of British Surnames published in 2009 described several cautions as you try to assign origins to your surnames of interest. See “Researchers Beware,” Family Tree (http://www.family-tree.co.uk), December 2014.
One of the areas he covers in considerable detail is place-names that become surnames: examples include names ending in ham, ley, ton, don, wick, hurst, thwaite. Consult the place-name indexes compiled to accompany the English and Welsh census reports. These government documents will be found as reference volumes in American libraries that subscribed to British government documents. Try your local genealogy library to be sure. Then consider the university and college libraries nearby. Also check WorldCat for copies nearest your zip code.
Titford’s article includes many names that have different origins than you might expect–with the caution that research on your surname could be quite beneficial to your genealogy.
Family Tree includes a column in each issue on surnames. With a “surname of the month” and comments by other experts in the field.
Your favorite British genealogist, Arlene Eakle. (All of my roots are British before 1850.)
PS Stay tuned and check back often for other insights and resources to chase your ancestors back before 1650.