Yes, you can `visit' yo wife in Canada after you have submitted the Outland package or send it from within Canada.
You can't legally move to Canada until you have your PR, so you really need to read up what you should and shouldn't do when you arrive at the border.
If you arrive after you have applied, you should be aware of how CBSA deals with a person (like you) that will have a `Dual Intent' to enter Canada:
http://www.cic.gc.ca/english/resources/tools/temp/visa/dual.asp
Lastly, you do not need a visitor visa, since you are a U.S. citizen. You simply present yourself to the CBSA officer at the border and see what s/he tells you. Unless told otherwise, you are entitled to stay for 6 months. If you are told otherwise, the officer will likely stamp your passport with a date that you must leave Canada by, but...you can apply to extend your stay prior to that date, citing that you have applied for spousal sponsorship. These requests are usually approved, but of course there is never a guarantee.
It's entirely possible that you can visit and remain in Canada during the entire process, albeit as a visitor without authorization to work, but...it really is the fastest way to get through what will undoubtedly be a roller coaster of an emotional ride.