I prefer books to all other methods of learning. Unfortunately there's only one PowerBASIC book
and it's not yet available.
Until the picture improvies, about the best a PowerBASIC programmer can do is to get the most
from other books - books which discuss programming in general and books on other languages where
the content is readily converted/translated into PowerBASIC.
The one book on PowerBASIC 9 is available from PowerBASIC, Inc. I'll keep watch for
any additions to this list.
Windows Programming Books
PowerBASIC lets you program at several levels. You can use the DDT statements which
shield programmers somewhat from the Windows API, or you can program directly with
the API using the techniques demonstrated in the Windows SDK.
The SDK programming approach is often preferred by more experienced programmers because
it provides a greater level of control on the resulting application.
These next few books provide full coverage of Windows programming techniques.
Generic Programming Books
This list of books provides the books most commonly recommended by programmers on
the web. The books cover all languages as well as all phases of software develoment.
Book Recommendations from Other Sites
These sites provide their own recommendations for book on programming. You might
find items of interest here, although none are specific to PowerBASIC.