I hope this will be informative to many people, as I found it difficult to exactly deal with the insurance limits and intricacies of shipping to PCGS from Canada.
First of all PCGS requires you ship by either:
"Registered Mail through the USPS" which means Canada Post
PCGS
PO Box 9458
Newport Beach, CA 92658
or"Federal Express using express services only (Overnight, 2-Day)" which means FedEx International Economy
Collectors Universe
7000 Barranca Pkwy
Irvine, CA 92618
HOLD FOR PICK-UP
They will not accept FedEx Ground, or any other shipping company. (I cannot verify this as it would be too risky to try)
Further instructions for reference:
http://www.PCGS.com/packageandmailcoinsNow for my story...

I had shipped coins to be graded back in 2012, but could not remember the process I had done, so it was as if it was the first time.
The easiest parts are:
-Signing up for a PCGS membership
-Filling out a online submission form
-Waiting for the discount submission vouchers in the mail (I suggest you signing up early for the membership to allow for the ~two weeks time it takes them to ship you your membership package and vouchers)
-Labelling, wrapping and packaging my shipment carefully
But when I got to the shipping stage there appeared to be no way to insure my 20 coins that totalled $14,000 CAD on their way to PCGS...
Canada post told me they can only insure up to $500 CAD maximum on collectable coins.
After a long call with FedEx (with the help of a nice owner at a FedEx shipping center) their limit on collectable coins was $1300 CAD.
I couldn't possibly live with myself if the coins were lost in the mail or stolen, so I needed to find a solution.
I had heard of "third party" shipping insurance companies such as ParcelPro... (as suggested in another thread by doubleeagle59: "It's pricey, not only because of their insurance rates, but also they insist the package must be sent Fedex Overnight, which isn't cheap.") but I wanted to do it by the book with FedEx. Maybe in the future I'll try ParcelPro and post about my experiences with them too.
I managed to get around FedEx's $1300 insurance limit by:
1. Creating a free 'Regular' or 'Individual' account by phoning into Fedex to obtain a 9 digit account number
2. Creating a shipment with 'FedEx Ship Manager Lite' - regular ship manager would not work
3. Entering all the details for the FedEx submission as outlined by PCGS (link above)
.....The most economical way to ship is 'FedEx International Economy'
4. Entering the type of shipment as "repair and return" (as it's not a commercial sale)
.....Make sure 'Hold for Pickup' option is selected
5. Indicating all duties, taxes and fees for customs would be paid by my 9 digit account number. I expect PCGS would not pay any duties or fees if they receive your package, and if they did they would either refuse the package or add the fees onto your grading invoice... so I just took care of that part myself.
6. Filling out the description of the coins to my best ability:
.....Numismatic Items sent for Appraisal - To be Returned
.....10 coins 1884-1907 (Canadian Copper Pennies) Valued $9000 CAD
.....10 coins 1925-1935 (Canadian Copper Pennies) Valued $5000 CAD
7. Since I was sending 20 coins worth $14000 CAD, I had to split the itemized list up into 20 items worth $700 each (totalling $14000) since that is the only way FedEx Ship Manager can understand it easily.
8. Attaching a Antiques declaration form as indicated by FedEx for coins 100 years or older to be exempt from duties/customs/taxes (I have uploaded it here for everyone's use
http://docdro.id/XmP1ZKx) That is why I split up my description, so the 'non-antique coins' would be charged taxes/duties/customs.
9. Printing out all the documents / put in my coin voucher into the box / final packaging
10. Dropping it off at the FedEx ship center
I know this must seem extreme to some

but I wanted to see what it actually took to get my package there properly.
Cost of shipping:
$565.10 fully insured two day overnight shipping + $47.36 in duties and taxes.
Cost of peace of mind: Priceless!

Currently all my coins were shipped and picked up quickly by PCGS. I have received the grades online under my order and waiting on them to ship it back to me (fully insured on the way back under PCGS's insurance).
I hope this was informative for some!
Thank you to gawd0wns & DEVLEC for motivating me to write this all out!
One side note: I have heard of many people talking about writing obscure descriptions on their packages such as metallic discs, or obsolete numismatic collectables... but in my experience, no one at FedEx or Customs knew what that was... and it delayed my shipment until I could clarify.
Some people are paranoid like me that writing "collectable coins worth $14000" is asking for it to be stolen, but I feel safe in FedEx's process and security.
I Would really like to hear from people who have used Canada Post with tracking or FedEx who have purchased shipping with a third party insurance company! Very curious!