The process starts with licensing. If you have little knowledge of firearms, I recommend taking the Canadian Firearms Safety Course (CFSC) and the Canadian Restricted Firearms Safety Course (CRFSC) - otherwise, you can challenge the examinations.
http://www.rcmp-grc.gc.ca/cfp-pcaf/safe_sur/cour-res-eng.htm Most gun clubs offer these courses and google will give you an exhaustive list as well. To own a handgun or any other restricted firearm in Canada, you need the restricted endorsement on your Possession and Acquisition Licence (RPAL). In general, you may own/possess a handgun in Canada for two reasons: target shooting or as part of a collection. To satisfy the Canadian Firearms Centre and the Chief Firearms Office in Ontario, you must either belong to a club or have sufficient knowledge of the firearm or its historical significance. Collectors are subject to a lot more scrutiny, inspection and transfer requests are often denied. For the target shooter, all you need is membership at and use of a shooting club. It is not enough to just be a member, but you must also use the range more than 3 times per year, IIRC.
Once you have a firearms licence with the restricted endorsement you may be able to purchase a handgun (restricted firearm). It must be stored unloaded, trigger locked and inside a securely locked container or room that is difficult to break open or into. If stored in a safe or vault designed for the secure storage of firearms, a trigger lock is not required. Again, depending on your reasons for acquiring a handgun, you need to be a member of a shooting club or recognized by the CFC and CFO as a collector. Restricted firearms can only be stored in your home and may not be removed from your home without the authorization of the CFO. They can only be loaded and discharged at a range that has been approved by the CFO.
If you join a shooting club, an additional restricted firearm handling safety course is required to apply for a long-term authorization to transport restricted firearms (LTATT). That takes about 6-8 weeks. Then an application can be made to the CFO for a LTATT. Without it, you cannot transport a restricted firearm to an approved range for target practice. Short-term authorizations to transport (STATT) restricted firearms are only issued to those transporting firearms to border crossings, between purchasers/sellers/address changes, gunsmiths, airports, etc. Restricted firearms must be transported unloaded, locked in a sturdy container that is hard to break open or into. Once you have a LTATT, you can transport a restricted firearm to and from any approved range in your province subject to any conditions it has - i.e. it has not expired, the firearms are registered to you, you remain a member in good standing at a shooting club and your firearms license is valid are the most common in Ontario. You must also take a reasonably direct route, in all the circumstances, to and from an authorized/approved destination. The process is as much hassle as it is worth to you. With all the advice out there, it's not so hard jumping through all the hoops. It's a great sport with a lot of great people from all walks of life.
Join the Canadian Gun Nutz forum for a wealth of information, links to retailers and access to the equipment exchange where firearms and other related items are listed for sale.
www.canadiangunnutz.com
Do not buy any firearms, ammunition, parts or scopes from the US - in most cases, you need to be a Federal Firearms Licensed dealer in the US and you must have approved export permits. The import process can also be complex. It is a convoluted and dangerous process - beware!