Well you missed the boom. Most of the companies that were hiring PHP programmers were startups and most of them have gone down the tubes, or at least stopped there expansion while they try to make a profit.
There are PHP jobs out there, but they are fewer and fewer each day. The problem is that most established companies don't want to risk anything on a new language, especially the way the economy is right now. What you need to do is convince your current employer what the benefits of using PHP are and what can be done with it. Then you will have a PHP job, and there will be one more company out there who is using PHP.
If everyone who reads this board convinced there company that PHP is the perfect tool for some job, maybe even for a project that hasn't even been thought of yet (like internal intranet based tools for the office), then there would be a much stronger call for PHP in the workplace.