I've been working on a PL/SQL web application for the past couple of weeks, and it has been a nice break from JAVA. I use the OWA (htp) packages to complete the web code. In my most recent application, I had the need for an auto complete text field which populates with an employee ID and name. Luckily, since PL/SQL web services are a breeze, this was an easy task!
If you've never created a PL/SQL web application before, I suggest you take a look at the references at this site: http://www.oracle-base.com/articles/9i/PLSQLWebToolkit9i.php as they will be able to assist you greatly. They are easy to create once you've got the hang of it.
All that is required to make a PL/SQL web service is a stored procedure. Actually, the best practice is to make a single PL/SQL package which contains all of your web service stored procedures. Your stored procedure is treated as an html page. The procedure simply accepts whatever parameters which are required to fullfill the CURSOR query and then displays the results in XML format.
In Part II of this blog, I will show an example!