I have been reading about David Kern`s book titled: ``Curriculum Development: A six-step approach``. I recommend all to read this reference. If one reads these six steps, understanding the ADDIE model becomes easy. David Kern lists the following steps in developing course curricula:
1. Problem Identification and General Needs Assessment
2. Targeted needs assessment (of learners and learning environment)
3. Educational objectives
4. educational strategies
5. Implementation
6. Evaluation

Reading the above steps, they are closely related to the ADDIE model. There are many other steps to developing a course like Ronald Harden`s Ten questions. what the ADDIE model does is to put all the segregated steps in other instructional design models into 5 broad and easily understandable steps that every body can adapt.

I also recommend a good reference that will make understanding the ADDIE model quite easy.

Mubuuke Aloysius