In Canada, Canada Computers is your best bet for finding the lowest price on computer parts. NCIX will sometimes be lower then CC, and they also allow a person to request a price match.
Also keep in mind that Canada Computers charges 3% on items so NCIX will figure that into their price match. My only qualm with Canada computer is that they seem to have a number of items out of stock, particularly cases and PSUs.
I purchased roughly half my parts at Canada Computer and the other half from NCIX who had stock of parts I was looking for. I also see Canada Computers upped their flat rate shipping fee (some areas excluded), from $4.99 to $6.99 which means you save a significant amount on shipping. NCIX however will cost a significant amount more depending on the size of the order, etc.
Also keep in mind, Canada Computers is Toronto based (warehouse), while NCIX is Vancouver.
Unfortunately Newegg does not ship to Canada and most times the cost of shipping and the brokerage fees will nullify any savings you might have received.
Also keep in mind that Newegg is a much larger company and is web based whereas Canada Computers up here is both retail and online as well as being a much smaller company. So prices will differentiate between the two as one will get a better stock price from their supplier then the other.