Scribus is an open source desktop publishing tool that helps you create professionally laid out documents, from simple documents to full blown magazines, corporate brochures or even books. Desktop publishing tools are not a replacement for word processors, instead they give you the freedom to create uniquely designed documents and help you manage large sets of text and graphic content. Scribus is similar to Adobe InDesign or Quarq Xpress and gives you a wide range of tools to layout content in either print or digital media form. Scribus is pretty easy to get to grips with and has good documentaton on the project website. The Scribus 1.3.5 beginners guide is a really handy guide through the workflow of desktop publishing and helps you clearly understand how to create professional looking results.
Inkscape is an open source 2D drawing tool that helps you create graphic designs, from simple buttons and logos to full blown posters and web page designs. Inkscape is similar to Adobe Illustrator or CorelDraw and gives you a vector based graphics tool that uses the W3C Scalable Vector Graphics (SVG) format.
Inkscape is easy to use, although learning the tricks that make designing a web site look great are more involved. Here is a book review for a new book about Inkscape.