PHP source from http://www.php.net/ (php-5.1.2.tar.gz).
Apache httpd from http://httpd.apache.org.net/ (apache_1.3.34.tar.gz).
Put them in a directory of choice, ie. ~/src, and unzip the files.
~/src$ tar -zxvf apache_1.3.34.tar.gz ~/src$ tar -zxvf php-5.1.2.tar.gz