Note:
Library and Archives Canada (LAC) is in the process of migrating their material to new servers. Maybe eventually the new site will work better, but until then, many researchers still use the old sites and old process because — although it is laborious — it works. So the old approach is posted here. When a new, truly better method is available, then we will post a how-to article on it.
Step 1
Start by doing a search on the person whose petition you are seeking. Try several searches with different spellings of both first and last names, and allow for mistakes in the transcriptions of the original documents regarding names, places, etc. (The search tool is not very sophisticated.)
Link to search page is here:
This will give you, among other vital info, the number of the microfilm on which the specific petition can be found. It will (likely) be accessed from this page or a subsequent page.

Step 2
Link to the (first page of the) list of microfilms (including hotlinks to each film):

Step 3
Click to the number of the film to which you have been directed and scroll through the images on that film to find the petition you are seeking. The petition number is typically written near the top of each page but the sequence may appear to be illogical.
Be forewarned: this is a slow and labour-intensive exercise. Adding to the challenge, these documents are mostly hand-written. With some patience you’ll get the hang of it.

