Packaging options for managed services are defined in JSR 109: Web Services for Java EE,
Version 1.3.
For services:
5.4.2 EJB Module Packaging
...the Web services deployment descriptor location within the EJB-JAR
file is META-INF/webservices.xml. The wsdl directory is located at
META-INF/wsdl.
5.4.3 Web App Module Packaging
...a Web services deployment descriptor is located in a WAR at
WEB-INF/webservices.xml and the wsdl directory is located at
WEB-INF/wsdl.
For clients:
A client can be any of the following: Java EE application client, web component, EJB component, or another Web service.
The location of the Web services client deployment descriptor in the
module is module specific. WSDL files are located relative to the root
of the module and are typically located in the wsdl directory that is
co-located with the module deployment descriptor or a subdirectory of
it.
Note that this spec restricts itself to Java EE clients; it doesn't mean that you can't have an unmanaged client where you provide the WSDL explicitly.
Cross-reference these specifications for more detail: