Addresses should definitely have their own table.
Have you considered using Postgres? It allows for table inheritance in
much the same way that inheritance works in OOP. You could have a parent
table (like a parent class) for People, and child tables (just like
child classes) for Employee,
PHP 5 Power Programming by Andi Gutmans, Stig Bakken, and Derick
Rethans may be worth the read for you. It doesn't mention an MVC, but
they do talk a little about patterns in PHP.
However, you probably won't find much in-depth coverage of patterns in
PHP. There are alot of good books written
