if you have not received word of approval as a sponsor (first stage in the process), then you will want to call the cic call center and inquire about your application. currently, they are processing november/december applications, so you are well beyond the posted processing time. there's a good chance they sent you the approval letter and it got lost in the mail (many people have been receiving it by regular mail lately).
i'm not sure where you are calling and what you mean by not having much luck. did you actually talk to a person and specifically ask about your application? you need to call the cic call center, not mississauga. The call center will be able to verify if your application is received, whether it's processed, or if it's not in the system.
if that doesn't result in anything, then the next step will be to call the canadian sponsor's member of parliament for them to inquire on your behalf. CIC must respond to MP requests.