"Orders" not showing in db

I am having similar issues with my "Orders" not showing in the database as the thread below. I am using PayPal Standard and I have done a couple of trial purchases and am receiving PayPal confirmations of them through email.

showthread.php?t=22328&highlight=orders

The following portion of the above thread may resolve this issue, but can you provide more information and/or direction on this. When I set-up eCart, I placed all the appropriate PayPal info that was requested. I found the PayPal's instructions for setting up a IPN account, but am not sure of what the correct "Notification URL" I should use? Does anything additional need to be done with the website code?

"I believe the issue is that you don't have IPN enabled in your PayPal settings.
You notice that under the Payment Gateway setting for PayPal standard there is a URL which is a URL to the IPN page. Have you already enabled IPN using the Provided URL?"

Additional info:
In the db, if I use the user profile page to populate the address, phone, etc., the fields get populated on the users table. However, when I go through a purchase transaction and provide the billing address/phone and the shipping address/phone, it does not populate the address fields in the users table or the orders table. At this moment, if I go through a purchase transaction with a required login (Registration info is: First Name, Last Name, Email, Password), the only fields that are populated on my orders table are: OrderID, OrderUserID, OrderShipping, OrderTax, and OrderDate. On the orderDetails table the populated fields are: DetailsID, DetailsOrderID, DetailQuantity, and DetailPrice. All other fields read NULL.

I don't know what I did wrong now:(

Thank you!