Pro sites Sign up Modification needed

Hi!
If a user comes back to get another site I need to give him some information and ask for patience due the large amount of data involved.
In sign-up.php I need to generate following text:

Get another The Art of Web Design site in minutes
Welcome back, manager. By filling out the form below, you can add another site to your account. There is no limit to the number of sites you can have, so create to your heart’s content, but write responsibly!
/*********Here the text needed*****************/
Be aware that we provide you with a very powerful website containing lots of sample images and ready to use templates. On slower internet connections the automatic generation of your new site may take several minutes to complete the uploading due to the rather large amount of data.
Please be patient until the installation process is fully completed.
We hope you enjoy your new site. Thanks!
/**************************************************/
Sites you are already a member of:
etc, etc

Can you please provide me with the php to make that change?
Thanks for your help
Peter