Why you want to get a new one? It is too old or something wrong with it?
Watch for the ad. in newspaper, flyer. The discount should coming out soon.
You should start researching the info about furnace. Call some HVAC company up and ask them to send a sales rep to you they will explain what kind of furnace would work for you.
Check out the web site from CMHC (a government agency)
Replacing Your Furnace | CMHC
I used Francis Home Enviroment a few years ago (replace my furnace), the furnace brand name is Lennox (very good reputation), the sales rep., service people and service were good (professional, courteous and on time) . I still use them for my regular maintaince (AC and furnace).
Service Experts Francis Home Environment
Happy shopping!