customise email template plugin needed

Hi, this might be a question that has been asked before, but I need help choosing a plugin that allows me to send emails to a specific user/users.

Basically I want type in the email address this email goes too, custom text that goes into the email body and the email is send to the user/users. For example personalized welcome message, or any type of correspondence. If this plugin also have a template, that would be a bonus. Any help appreciated.