I agree that it is important to examine what you are trying to do with XML. XMLSpy is available in three different versions that offer different capabilities depending on your needs.
Can you explain more about what you need? Somehow the question got focused on PDF generation, and a little more input is needed there!
If you are looking for PDF generation from XML though, you might want to take a look at Altova's graphical
stylesheet designer, StyleVision. This lets you generate XML or database content in HTML, RTF, PDF, and OOXML based on a single stylesheet that you create visually - using drag and drop, right click, entry helpers, etc. The XSLT and XSL:FO code is written behind the scenes and the resulting documents can be viewed at any time during the design process.