Apple store pick up charges $1.00? Does anyone know why this is showing up on my cc account?

Payment card authorizing holds

http://support.apple.com/kb/HT3702

You are most welcome 🙂

I am charged twice for the same apple ID, second time for just changing the credit card details with the account. is it normal?

Is the $1 value is just holding or charged on the credit card?

Authorization Hold

If you update your billing information, the iTunes Store will place an authorization hold on your payment card account, usually in the amount of 1 USD, to verify your account information. It will be credited back to your account later.

http://support.apple.com/kb/HT3702