LibreOffice - Writer - Open-source cross-platform word processor.
PDF Joiner - This online tool allows you to join several PDF documents into a single file, free of charge.
Microsoft Word - Microsoft Word is a commercial word document processor for Windows.
DocuPUB - DocuPUB is an online file converter, file merger, file compressor, and file resizing tool.
Google Docs - Create a new document and edit with others at the same time -- from your computer, phone or tablet. Get stuff done with or without an internet connection. Use Docs to edit Word files. Free from Google.
PDFill - Open, View, Edit, Save and Print PDF Documents without Adobe Acrobat