OurOntario.ca has partnered with the Barrie Public Library and the Orillia Public Library to make their local newspaper collections available online. The site indicates that coverage among the communities varies but can include indexing of news articles; births, marriages and deaths (with clippings); and full page/issue access.
Simcoe County communities currently available include:

  • Barrie (Full issues, 1855 – 1979, BMD index, 1847 – 1968)
    includes:
    – Barrie Advance
    – Barrie Examiner
    – Barrie Herald
    – Barrie Magnet
    – Barrie Saturday Morning
    – Northern Advance
    – Northern Gazette
    – Spirit of the Ages
  • Orillia (News & BMD index, 1868 – current )
    includes:
    – Coldwater Courier
    – Country Courier
    – Daily Packet & Times
    – Northern Light
    – Orillia Connection
    – Orillia Daily Times
    – Orillia Expositor
    – Orillia Journal
    – Orillia Month
    – Orillia Newsletter
    – Orillia Newsmagazine
    – Orillia Packet
    – Orillia Sentinel
    – Orillia Showcase
    – Orillia Sun
    – Orillia Times
    – Orillia Weekly Reporter
    – Simcoe Report on Business
    – Summer Sun
    – Wednesday Nighter

The OurOntario.ca newspaper collection includes other communities as well. Check their site for details.