http://fdegrelle.over-blog.com/article-26471694.html

Here is a few links to point to some Forms books (Amazon):
Oracle Developer Forms Techniques (Paperback)
Oracle Forms Developer — The Complete Video Course
Oracle Forms Interactive Workbook (Interactive Workbook Series) (Paperback)
Programming with Oracle Developer (Sams White Book) (Paperback)
Oracle Developer Advanced Forms and Reports (Paperback)
Developing Oracle Forms Applications (Paperback)