Return to online journaling....

This will be a purely research focused journal. So don't expect amusing anecdotes of what happened to me at Starbucks or at a party. Or my musings on life in general.
I would like to invite historians (and anyone else) to comment and send advice.

Right now, I have been working on a small article which has brought me into the 'land of the living' as a historian, or rather, into the time period in which participants may still be alive. I looked up one person in the phone directory, I don't know if it's the same person, but the age range is right (I paid the 95c to some online people-finder skip tracer directory) and it is the same area, so it's possible.
I looked up the address, from 50 years ago, and the house is still there (thanks, Google Street view!).
I feel creepy and stalkerish: I want to know as a historian, but at the same time, how much can I know? What if it is the same person - am I going to pick up the phone and call? (I don't think so - at what point does my 'right' to scholarly enquiry override my instinct not to harass the elderly?).
I realise that historians who do oral history and deal with contemporary sources deal with this all the time. But I feel discomfort, like it is invasive for me to be writing about the life of someone still living and presenting it as a historical artefact.