If you use Eclipse as editor you can enable a wsdl plug in that allows you creating wsdl files in a "design" mode. This way you don't have to type the entire wsdl which is a rather difficult and error-prone task.
The wsdl resides on the backend server that provides you with data you are asking for. The fronend that connects to the service may be written in PHP too and should provide the forms to ask for the info from the server.
A good resource for PHP questions is of course
http://php.net/manual/en/soapclient.soapclient.php
If you want to transfer confidential data you should consider using ssl encrypted traffic. If you are the only consumer of the services you can create a self-signed certificate for the encryption. You will find how to create that at apache.org.
