Trouble installing OCI8 support w/ PHP Apache
 

I have searched the world over for the solution to my issue, but I have come up empty handed.

OS is Red Hat, I am using Apache and PHP RPMs. I have Oracle Instant Client installed, environment variable set, and I can access my Oracle db through SqlPlus. Apache and PHP work great, PHP has Mysql support and I can access Mysql no problem.

I am new to Linux so be gentle. I have read I can add OCI8 via ./configure with PHP, but I have no idea where PHP is installed.

Can someone point me in the right direction?

I've never used php with oracle, but I'll try to help.
You can run:
to see if php was compiled with oci8 support. If not (most likely), you should d/l the source code, matching your version of php, from http://www.php.net/ and compile it by adding "--with-oci8" or something like "--with-oci8=instantclient,/path/to/oic/lib" to the output of the above command. I.e. you should run something like:
Then run "make", "make install".
I guess you have to uninstall the php you're now using before running "make install", but keep the rpm handy in case something goes wrong.