I have recently begun assembling an index of all known members of the Lenaghan family living in County Down before 1840. Thus far I have used Freeholder records, tithe records, Flax grants, British military pension records, and a few others.
If you have any primary documention mentioning a member of the family in County Down before 1840, please let me know. And of course I would be willing to share with you the results of my research.
On a personal note -- I am particularly interested in hearing from people who connected with the Lenaghan family that resided in Kilmegan parish.
-- James Lenaghan