how send email for web intelligence report to multiple users

Hi

I want to send a email to multiple users with an web intelligence report as attachment

but the problem is i can type the users email ids and send ,but i dont want to do that

since my users list for whom i send the mails changes dynamically,

hence can any body help me out is there any option like address book as we have in outlook

or can i store users email id in any file or any other such that i dont have to type the email ids all the time and add the users from that file to 'TO' list of email