For those with kids here is our experience with schools:
If you're interested in the ESL Pre-School from the Catholic School System, and your plan is to be here by March this year, you should be perfectly fine to register her for the next school year that will start in September 2011, because of her date of birth. So just as I mentioned before, she'll have to be the required age by March 1 of the following year... like this:
* Pre-School if the child is 4 yrs old by 03-01 2012 *Kindergarten if child is 5 by 03-01-2012 *Grade 1 if child is 6 by 03-01-2012, and so on.
Both School Systems have an office where newcomers must register the children in order to enroll in any of their schools.
Check their websites: http://www.cssd.ab.ca/default.asp?V_ITEM_ID=253
Eventhough the Preschool program is not mentioned in the Catholic website they do have it for sure. You might want to check with the Public Schools to see if they have such program available, as far as I know they only have Preschool for children with disabilities or special needs.
About preschools in churches and community centers, they usually have on-going registration until their spaces are full, then they start with the waiting lists; some places may have spots available at anytime. It is always on a first come first served basis. I think most are flexible about enrolling a child to start in any month of the school year, but that's pretty much their decision and of course depending on availability. They run with the schools calendar from September to June. All schools (church based, community center based, Catholic, Public, private) start registration in January-February for the school year that starts the next fall. However, the schools will always offer spaces to register children in Elementary, Jr High, and High School, in any month that schools are in session, because they are government regulated and they can't deny education to a child. So for those of you who are arriving in Canada during the school year, do not worry about the kids not having a school to attend, or having to wait to enroll. They should be able to enter school right after you arrive, except if it's in the summer months!!
I just found this other Preschool websites that may be of your interest:http://www.pre-kindergartened.com/
<--- this one seems to be a privately run program with locations in some of the Public Schools, and http://www.calgaryarea.com/calgary_preschools.asp
About the car... you don't need to buy a car first... but I can certainly say that a car is usually most convenient. You'll have to see what the family dynamics will be like... for example, are you and your wife both planning to work? (keep in mind that preschool is only for 2 and a half hours a day 2, 3, or 5 days a week), Do both of you drive? If you get a job that you need to drive to, and you only have one car then your wife may have to walk or take the bus with your daughter to and from school...even in ugly weather. By the way, public transportation is pretty good and accessible, I would say it's way better than in some major cities in the US.
My advice would be: check what area of the city your are planing to live, check which schools are in the area and if they have the mentioned program available. Check community centers and churches also in the same area to see if they have preschools, check availability or waiting lists, curriculum and fees, and then hopefully find a place to live that is close, walking distance if possible, that makes it really convenient specially when there is only one car for the family, or when there is bad weather conditions (schools close very rarely!). Here it can be -40 C, 20 cm of snow, or snowing heavily.... and the kids will still go to school... people go to work... people go grocery shopping, etc..
Best of luck in your search, I hope this guides you well or at least gives you a starting point!