PDF Combiner is a user-friendly, GUI-based tool built in
PDF Combiner is a user-friendly open source free to use, GUI-based tool for combining, pdf to excel, pdf to word, image to pdf, zip, unzip annotate and splitting PDF files. It is easy to use, supports multiple file insert and delete and process, and allows you to adjust the order of files before combining.
JPDF Export is a java library built on the famous iText library. It provides simple functions that can be used to build complex pdf files. It also provides simple classes to merge, split and convert pdf files
Jacrobat is a free open source PDF editor that will support all functionalities of a simple word processor. Advanced functionalities will be added as the project matures.