The first thing you should do is set yourself up with a server, so you can test your work locally.
If you're running Windows, Sourceforge has some binary installers that will get you up and running with minimal fuss.
http://sourceforge.net/projects/phptriad/
...That is if all you're concerned about is getting to work learning. Installing Apache/PHP/mySQL manually is an adventure that you can probably do without.
If you're running Linux, most distros will install it all for you.
When you're ready to get to work, get to Googling. "PHP tutorial" is an excellent search term. And if you want, i can give you all my bookmarks.
The best book i've found for a Newbie is "Build your own Database Driven Website using PHP & MySQL " by Kevin Yank. He gives away the first couple chapters here:
http://www.sitepoint.com/article/525
...and then you need to buy the book. If/when you do that, i highly recommend reading the ENTIRE book, and completing all the examples. This is hard-won advice; i didn't do that and instead went from tutorial to example to snippet, all over the web, and it shows.
Good Luck
JB
