OpenOffice.org is a free and open source office suite. It has professional features, and can be downloaded for free, or you can purchase a CD or resource kit. You could also purchase StarOffice, which is now based on OpenOffice.org.
The suite includes everything you will need to do word processing, spreadsheets, presentations, equation editing and a drawings. It opens and saves to most major formats such as MS Office and PDF. It includes comprehensive help, and spell checking in at least 15 languages. It also runs on many major operating systems, including Windows, Linux, Linux PPC, FreeBSD, Mac OS X, and Solaris (Intel or Sparc).
OpenOffice.org documentation.
Dictionaries for OpenOffice.org.
Taming OpenOffice.org, and creating and using master documents in OOoWriter.
The OpenOffice.org documentation project.
Icons, Graphics, Banners and other marketing materials for OpenOffice.org.
Information, training and books for OpenOffice.org by Solveig Haughland.
Goodies, templates, macros and more from Travis Bauer.
dMaths add-on for spreadsheet formulas and curve tracing.
Info's to OpenOffice from EDP - systems Kienlein.
You can use MySQL and OpenOffice instead of MS-Access for databases. Starting to use MySQL data base on Windows platforms is very quick and easy, according to this howto.
User mailing list for questions and answers. If you prefer the mailing list as a newsgroup, Gmane provides such a free service. The news server is at news.gmane.org and the list is known as gmane.comp.openoffice.questions. You can also search this mailing list. There are other mailing lists for announcements, website, and various other OpenOffice.org projects.
Instructions on how to enable the "DocBook File" filter.
Guides for StarOffice in PDF format.
API reference information. This is a good place to start looking for programming information.
Tutorial for the API (PDF format).
Office Automation Tutorial.
Older API information.
How to Use basic macros (writer document).
Andrew Brown's Useful macros.
Collections of macros, scripts, StarBasic, and information related to OpenOffice.
Utility Scripts contributed by the OpenOffice.org community. This page contains downloads of utility scripts that have been contributed by the OpenOffice.org community. These scripts are intended to demonstrate how to write Java (or the dynamically-typed Beanshell) scripts for OpenOffice, with full access to both the OpenOffice.org API and the Java APIs. The scripts are for use with the Early Developer Release 0.2 of the Office Scripting Framework and all subsequent releases. The framework requires OpenOffice.org 644 or above installed.