Help with a PHP API integration setup

I need to create a form that checks if an email address exists on a list, whether it be a subscribe, unsubscribe or suppressed list. If the email does not exist, add it to a list, if it does exist, show error with words "this email address is used on (name of list)."

Can anyone help? Or write (QUOTE)? License (Only if you have a working version that you use)? Or let me know if I can download or install on a server the appropriate script for this please? Quotes will be accepted however please note that this is not a project set, meaning, I do not have the approval to make this a billable project, so this is not spec work. If you have links that you are willing to share, i would greatly appreciate.

Thank you very much!

Frederick Polk, One Black Crayon

Join 150,000 companies around the world that use Campaign Monitor to run email marketing campaigns that deliver results for their business.

Get started for free
1-888-533-8098