The province of Manitoba's Vital Stats site is an amazing resource for people who have ancestors in Manitoba. Birth records up to 100 years ago, marriage records up to 80 years ago, and death records up to 70 years ago are available for searching. Unfortunately, most of my family lines were not in Manitoba yet that long ago, but a few of them were, and this site has been extremely useful for those families.
First, select which type of record you want to search for: birth, marriage, or death. Next, you can search by any combination of the following fields: last name, given names, place (city), and date (year). I recommend leaving some fields blank if you don't find what you're looking for right away. You could have a date wrong, or they could have a name spelled wrong (that's happened to me).
It can also be useful to do more general searches. I searched for all birth records with the last name Daigneault in St. Francois Xavier, and found not only the birth records for most of the Daigneaults I already had in my tree, but also some others, who probably died as children, since they weren't in any census records.
Unfortunately, you don't get all the information for free. You'll get names, dates, and locations. For birth records you'll usually get the mother's name. To get the rest, you can order the record, which costs $12. I haven't ordered any yet, so I can't say much about what you get then (I'll update this post when I do order some). $12 a record adds up fast, so I haven't decided which records I want to invest in right now. I'll probably start with records pertaining to my direct ancestors.
Even if you can't afford to order a bunch of records, this website is extremely valuable. Without paying a cent you can find exact dates of birth, marriage, and death, and often you can find middle names you didn't know about, or find out that what you thought was an ancestor's first name was really their middle name. (That happens a whole lot in my French ancestry, where pretty much every child was named Marie or Joseph, and they went by their middle names to tell them apart. Way to go, French Catholics, with your crazy ideas!)
Note: I have not actually looked for these at the Manitoba Archives yet, so it's quite possible that you can view the records there in full for free. I'll have to plan a day trip there sometime soon!