A little gem found in one of my favourite sites, archive.org is The Story of Dundas: Being a History of the. County of Dundas from 1784 to 1904 by J. Smith Carter, published in 1905. Especially useful are the mini biographies found in the appendixes, and a nice plus are the many photographs of early settlers and of the professionals — doctors, dentists etc, in the county. If you’ve got Dundas ancestors, take a look here and download a copy in a variety of formats.
You can always find something interesting and helpful at Ottawa Valley Irish blog. The latest of helpful resources is a transcription of Marriage Records from the Fitzroy Harbour Catholic Mission. While I knew the Mission served the Harbour area, I learned from the blog that it also served Catholics from the other side of the Ottawa River in Quyon, Quebec area.
If you’d like to take a read yourself and explore the 1852-1856 marriage records, find your way here.