membership communication constants

HI

I would like to display certain information in the email (membership communication)thats sent out when a person subscribes to a plan , i can see the available constants , but i also want to display the following information, is there anyway i can do this?

information i want to display

Plan: (this can be done using existing constant)

Amount: To display plan price

Expires : when the plan will expire

login information ie

username

password

any help on this would be greatly appreciated