custom scripts

I have idevspot bizdirectory software (written in php) installed on my site and I am looking for three scripts to help me customize the software. ? 1. The first script is to allow users to contact listing owners by email. I want to place a link on the listing page that says contact (whatever the company name is) and when the user clicks on this, a message box will show up that asks the user for their name, email address and the message. The message will be sent to listing owner. 2. Second script is a user admin panel script that will allow users to register, view/edit account details, add listings to their favorites and later view them, view messages and reply, and integrate the login process into the existing software. When a listing owner or user logs in I want them to be taken to the appropriate admin area after login or when they click on my account from the top of the page. 3. The third script I need is a script adding the ability to view and reply to messages to the listing owner admin area so listing owners can receive and reply to messages from users.