Depending on how long it has been since you received the email from Apple, it may take some time before the shipper's web site shows the tracking information.
Tracking numbers take a little while to be activated. Just because you have a number does not mean the shipping facility (fedex/ups/dhl/etc...) has the item. The number is generated when Apple sends the item to the shipping facility. Give it a few days.
Usually when you click on the tracking number it will bring you to the shippers web site. Try going to My UPS and entering the tracking number.
You say you "just" ordered those items. Note that it can take some time - hours, maybe a day - before the carrier will have it show up in their system.
Tracking an apple package.
