phpmsql & billing/contacts

With php/mysql, I have a contacts table/also table for information for what is purchased in regard to the site. (number of orders, order dates, etc) However nothing related to billing information. note: some accounts will be paid prior to providing the service while others receivables.

Yet I am unsure about integrating billing information; generating bills, according to tracking payment status.

Presently I have Outlook for email (only some duplicate contacts, the duplicate entries I plan to eliminate) and am also looking into Quick BooksPro, and ACT to manage contacts.

This of course is a redundancy question.

Is a way to import table data into Outlook? Also I would like to be able to track company correspondances the way ACT can be implemented detail phone conversations/email correspondances listed neatly organized per date/what was said, etc., (haven't found a download for Outlook that can accomplish anything near this. --perhaps Microsoft Contacts Mgr, but this is only a guess which I haven't seen, and this may require purchasing an entire new Office small business version for it, I don't know.)

Does anybody have suggestions on how to integrate MYSQL table date with billing/email/company contacts that can be used for notating phone conversations as well? A table dedicated for payment, and an interface page using calculations from these column values? But how to integrate this with Contacts/emails/phone conversations/payment status or history of payments is the general question.