Do you have Oracle database or Oracle Instant Client libraries? You need one or the other. See steps 12 & 13 of http://www.oracle.com/technetwork/articles/technote-php-instant-084410.html
If you already have an Oracle database on another, remote machine, then I recommend using Instant Client on your PHP/Apache machine. Instant Client can be put anywhere as long as PATH points to it. The path you are seeing in the Configure Command message is where the builder of the PHP DLLs had it. You can use another directory.
Also see http://www.oracle.com/technetwork/topics/php/underground-php-oracle-manual-098250.html