Reply To: Kincora
Have you tried the Historical Picture Company? Its a shop located on Ormond Quay Lower, a few doors downriver from Capel Street bridge. They have an enormous selection of old photos for sale, and are very good for photos of old Dublin. All the images are filed by area.
There is another historical photo shop at the top of Capel Street near where it joins Bolton Street.
The architectural archive on Merrion square is always a good bet but ring first and check opening hours.