New to PHP, just looking for resources is all =)

Hi there, I am new to PHP and mySQL. I am a fairly quick learner and have set up a script to add/modify/delete entries from a mySQL database and display them in a table. My first question is, where or how can I get information on how to only allow certain people to add and then modify what they have added based on their user name and password? Right now, anyone use the script and add/delete/modify all entries. I need to create a way for everyone to be able to register a username then be able to login. The other thing I wanted to know was where I could get any information on building a completely database driven site. A lot of sites have references to content but none that I have come across tell you how to use the database to display things like images, imagebars, buttons, and so on. I am not asking for any one-on-one help here(I realize most of you have lives and dont have the time for that, although I would most certainly appreciate it, heh =)) Any links or references you could provide would be MOST helpful. Also any good books on PHP and building database driven websites using PHP and mySQL. Thanks in advance, Pete