If you want to use JDeveloper 11g for Soa and/or BPM Development you need to download the SOA JDev Extension for the SOA Composite Designer and the BPM JDev extension for BPM Studio.
In all the documentation you'll find, you see an explanation on how to download them using the Help/Update utilities of JDeveloper. This might be neat and user-friendly for updating one JDeveloper instance where you have a fast internet access. But it is not so handy if you have to provide these extensions to multiple JDeveloper instances for a course for example. Then it is handy when you're able to download them and provide them on a stick.
I found these files on this JDeveloper extension page (just using Google).
So I downloaded the latest versions on my harddisk at home, where I have a good internet access. I hope this page is on-line indefinately.