I'm working on an event management system written primarily in PHP/mySQL with some help from javascript and CSS here and there.

As it stands now, there are two main sections of the system, one holds contact information and one holds event information with links to specific contacts. These links fall under subsections for the event such as "supporting staff", "production crew", "venue contacts" and so forth.

MY QUESTION IS: What is an intuitive way to allow the user to enter contact details while they are filling out the event information?

For instance, a user might be entering details about a concert and want to add a tag to the "supporting staff" area that links to the lighting guy's contact information. This is relatively easy implementation wise if the lighting guy already has a contact profile in the contact database, however if this information still needs to be added, what should I do?

I had thought of having an 'add user' form popup if the user doesn't already exist, but popups can get hidden or blocked and confuse users.

I thought of extending the add event form to accommodate the user information, but many of the contacts have 2-3 phones, 2-3 addresses, several special notes, and the form would get quite long, illogical and unmanageable.

I had also thought of having a secondary step in submitting the form that prompts the user to complete contact information, but I hadn't thought of a good way to do this for multiple contacts that don't exist that is clear and concise.

I'm looking for that professional approach that "just makes sense", where the user doesn't have to think about the system, it just works.

Any help on refining any of the above procedures, or an idea for a completely new approach would be greatly appreciated.

Thank you.