My husband has started the process for sponsoring me to immigrate to Canada. We are currently living in the US and therefore have decided to take the Outland route.
Hopefully you know that your husband has to be a Canadian citizen, not just a PR (permanent resident), in order to sponsor you while living outside of Canada. And if he's a citizen sponsoring you from outside Canada, he will need to demonstrate to the best of his ability that you guys will, indeed, settle in Canada once you receive your PR status. This can be demonstrated by outlining your settlement plans, showing a lease, job offer, letters of support from his family there (if applicable), etc. (Mentioning this just in case.)
Assuming we are approved, we are wondering about the timeline for immigration. Specifically, once our paperwork is processed/approved, how long do we have to move to Canada? Is there an expiration date on entry into Canada under this immigration class?
How long it actually takes them to process your file, approve you (hopefully), and issue your visa... depends on way too many factors, so none of us can say for sure. It could be anywhere from 4 to 11 months.
But once they issue you your PR visa, it WILL have an expiry date on it. This date will correspond to either the 1 year anniversary of when you had your medical done, OR your passport expiration date--whichever's sooner. You'll need to land in Canada before that visa expires in order to officially become a PR, but you don't have to stay; you CAN land, turn around and go back to the States to finish tying up loose ends, etc before returning to Canada.
Also, what are the stipulations for me upon arrival to Canada? Will I be able to visit my family in the US after I've immigrated? Do I have to stay in Canada for a minimum period before I can travel?
Of course you can visit your family in the States. Just because you've immigrated to Canada, doesn't mean you're STUCK there. You don't have to stay in Canada for any set amount of time right after you've landed; like I said above, you could even land, then turn right around and leave again. The only thing you need to worry about is maintaining your PR status. You do need to be residing in Canada for 2 years within a 5 year period in order to retain your PR status.
Hopefully that's enough to get you started. Others may chime in with even more info as well. Good luck!