Researching a deed in York County is pretty easy from 1960-the present. For Kennebunkport, Wells, Ogunquit, Start with the appraisal database Vision Appraisal Database to learn the street address of the house or the owners name, when they bought it and to see a picture of the house. Then go to the York County Registry of Deeds and sign up for a free account. Read the deeds associated with the names you found on the appraisal database until you find the correct deed. It will refer to a previous deed. Deeds are online only back as far as 1960 but you can go to the York County Registry of Deeds in the Alfred Courthouse Alfred, Maine to see the rest, all the way back to the earliest deeds. Google Books has early York Deeds online.
Book I 1642-1666 Book II 1666-1676 Book III 1676-1684 Book IV 1684-1699 Book V 1680-1699 Book VI 1687-1703 Book VII 1703-1713 Book VIII 1685-1716 Book IX 1717-1720 Book X 1719-1722 Book XI 1722-1726 Book XII Part 1 Book XII Part 2 Book XIII Book XIV Book XV Book XVI Book XVII Book XVIII 1736-1737