Don't have an Ancestry.com subscription? Good news! Canadian Passenger lists 1925-1935 are now online and indexed at the Library and Archives Canada under Microform Digitization
First you must conduct a search for your immigrant ancestor in the new online index
After you find your ancestor in the new online index you need to copy all the relevant information and then search the online digitized microfilm. You need to carefully note the Microfilm #, Vol # and Page # for your ancestor from the index entry. You will find the Vol and page #s at the top right of each manifest sheet once you are at the microfilm digitized copy.
Caveat: This index is ONLY for new immigrants to Canada. Families who travelled to Europe and back to Canada are not included
I searched http://www.collectionscanada.gc.ca/databases/immigration1925/index-e.html for my great grandmother Sarah Simpson. From the search results I chose this entry:
Given Name: Sarah J.
Date of Arrival: 1928/10/22 (YYYY/MM/DD)
Port of Arrival: Quebec
Ship: ASCANIA, Cunard
Reference: RG76 - IMMIGRATION, series C-1-a Volume: 1928
Page Number: 16
Microfilm reel: T-14750
Then I went to http://www.collectionscanada.gc.ca/microform-digitization/index-e.html and selected BROWSE BY TITLE then picked Passenger Lists: Quebec City (1925 -1935).
The new page shows me the T numbers for the microfilm so I
clicked on T 14750 as indicated in the index results.
The film shows there are 652 pages. I wanted page 16 so I entered it in the field provided. The manifest page showed on the right hand top that this wasVol 28 page 26 so I knew I was on the wrong page
I want Vol 29 page 16. I played around with page numbers until I got to Vol. 29 page 256. That's too far so I just began entering page numbers decreasing by 100 until I got to page 39 in Vo. 29, then it was easy to get to page 16
And there she was, my great grandma Sarah J Simpson listed as
"mother, age 66, widow, born Ramsgate England, having been in Canada previously from Aug-Nov 1926 at 2 Bala Ave, Mount Dennis, W. Toronto, passage paid by her son Mr E. Simpson, 2 Bernice Cres, Toronto, gives her nearest relative in England as her dau. Mrs. Bruce Walker 164 Homewood Road,Waltham Cross, Herts"
Her passport number is given, also a file number, she has 100 pounds and is a landed immigrant, a housekeeper in England and intends to be one again in Canada. Now I have something new to go on, the fact that she was in Canada in 1926. I should be able to find her in these new online records.