So you already did the tutorials, wrote a basic application and have a basic understanding of ADF? Well here is your chance to go to the next level of knowledge.
The JDeveloper product management team has started producing a series of recorded online seminars under the title "ADF Insider".
In these seminars we are trying to target specific topics that you are likely to encounter in more advanced ADF work - currently you can find sessions about the internal workings of the ADF Binding layer, skinning ADF Faces, security in ADF applications, and integration with the SOA suite, and more topics are in the works.
Check them out on the ADF Insider page on OTN.