why can't I check on where the pkg is when she said she mailed it??
Delivery confirmation is just that--confirmation for the seller that a package was delivered. The package is scanned upon shipping (or when entered into the computer) and again when it is delivered to the customer. It usually does not provide tracking information. I say usually because some post offices will scan all packages and others don't.
On Monday I received an email saying the buyer printed out a receipt and gave me a tracking number
I'm sure the package was shipped on Monday. Packages must be shipped the day the postage is printed--unless one wants to go through all the trouble of changing the date, which to me is a real pain in the rear.
Insurance will only cover what you actually paid for the item. The value does not matter. Shipping costs are excluded.
I wouldn't worry at this point. I'll bet anything your package arrives sometime later this week.