Thanks to this Cullen genealogy blog, I got in touch with Pearse Cullen of Northern Ireland (See his comment on Cullen's point altar field).
It's hard to believe that he is new to genealogy research because he's so interested and good at it. I found a cheap ticket to Dublin on Washington's Birthday weekend, and drove up to Tyrone to meet Pearse and his family. It had been almost 18 years since I last visited, but the area was beautiful as I remembered. This time Pearse and I had figured out how I was related to everybody--when I met his uncle Vince Cullen back in 1989, we suspected a connection but weren't sure exactly how.
Here's a picture of me and Pearse approaching the field of our ancestor, Thomas Cullen. (Pearse's relatives remember when Thomas' house still standing here, but today only the foundation remains). More pictures are available, just send me an email if you'd like the link.
(temporarily unable to upload pictures to blog--check back later)