If you don't have it you need to go it. The entire PHP manual is downloadable as a Windows help file or PalmPilot Database file. This is something that will definitely make a difference in your PHP life. Now to get a C++,Perl,Java,Python file like this. Well, probably not! Anyway, happy coding!
PHP Manual
Not quite sure where this came from, but it's good advice.
RTFM!
And for all you absentminded coders out there (I'm not only the president, I'm a member): If you just can't remember how to do the Levenshteinian comparison or how many arguments can be given to ibase_connect (seven, by the way) there is the always usefull: http://www.php.net/quickref
-Ben