I looked into this a bit recently and found that the best priced systems that were 'all in one' - ie I didn't need to know exactly which components I needed, was Costco. There were other places that might have been cheaper, but you had to buy the dvr, and each camera, mount and power supply etc separately and it was really confusing for me.
http://www.costco.ca/Common/Category...100&lang=en-CA
Looks like under $1k should be that bad to hit, depending on what exactly you need in terms of number of cameras etc