New on the Ontario Genealogy Society (OGS) site at http://ogs.on.ca/services/1812-militia.php they have a Records Page, and today, they have added a "collection of War of 1812 Militia Documents".
The person who has worked hard, and many hours transcribing the Records from the Library and Archives Canada is Genealogist Fred Blair.
The first two sets of Records are from the York Militia, and they are -
2nd Regiment of York Militia – Payroll at http://ogs.on.ca/services/pdfs/2nd-regiment-Payrolls.pdf
2nd Regiment of York Militia and 5th Regiment of Lincoln Militia - Flank Companies and Others at http://ogs.on.ca/services/pdfs/2ndYork-5thLincoln-Flank-Companies.pdf
He offered them to the OGS with the understanding that they would be available to ALL researchers – free of charge!
I went and took a look at them myself, and Fred did an impressive job. Besides transcribing the records, he also put his own notes in with the Records, and you should read them to see if they apply to the ancestor you may be looking for in your family history.
This is just the beginning of the Records he will be allowing the OGS to place on their site, so stayed tuned as Canada goes into the 200th Anniversary of the War of 1812 in 2012.