check your listing for the address you quoted for paypal payments - sounds as though you may have made an error with the email address

I wonder if you can help me. I am all new to selling on ebay. I have sold some items yesterday and got this message today saying that my payment was initiated on 11-jul and is being processed through paypal. So far when I look at my paypal account there are no payments. How long does it takes for payment to show up on paypal? Do I need to do anything other then wait for the payment to show up on my account? I just don't want to send the item before I make sure I received the payment.

changing your email with paypal and ebay doesn't change it on the selling form, you have to do that as you list.
If you still have access to that address you can add it to your paypal account ( you can have up to 8 addresses registered on one paypal account ) and the payments should come through.
If you can't get access to it then all you can do is ask your buyer to cancel their payment and ask if they would be prepared to send payment to the correct address - don't be surprised if they refuse as you can't mention the ebay deal that way just "goods".