I went through the Intro Tour. Find it very interesting. But, like in the song The Godfather; Where Do I Begin?

Sounds like you began at the right place. By "intro tour" we assume you refer to the Harmony 1 tour; that is a good place to start. Look for more tours in the near future. In the mean time, may we suggest taking a look at the section on Rhythm. Start with Basic Materials, and work through the "Footsies" until you have understood and felt the meaning of rhythmic levels. This will give you a very good foundation upon which to build other Music Novatory concepts.

The material in the database is very technical. Is there a way to assimilate all this for a beginner like me? What do you suggest?

Take it slow. The information contained on this website represents decades of research and formulation. It would take years to assimilate it all. Music is a complex and multi-faceted phenomenon. But the good news is that it is all generated from simple building blocks, so the beginner can progress through the material starting from the simple, and then gradually, move to the more complex. the sections on Harmony and Rhythm both have chapters called Basic Materials. These would be a good place to start. Also, once more Guided Tours are introduced, you will find some review exercises located at the end of each tour. These are highly recommended in order to self-test your understanding.

The part on Time and Pitch made sense to me on a conceptual level, but when I tried to go into the specifics like on the Rhythm pages I quickly became overwhelmed. Maybe it's because I don't have much previous exposure to music theory.

It is understandable that someone new to music theory would find some of the concepts here a bit overwhelming at first. To be honest with you, some of the concepts here on this site will probably seem overwhelming (at first) to some music theory veterans as well, because many of the ideas expressed here are new and not what has traditionally been taught. We hope that the majority of our visitors will find the theory of music presented here to be logical, comprehensive, and practical. Part of the reason you may feel overwhelmed is that the material is presented here in a very concentrated and streamlined manner. You may have to go very slowly and read some sentences over a number of times in order to fully understand their meaning. Also, the examples and exercises, especially in the section on Rhythm that you mentioned, will help to give you the "feel" of what we are talking about even if you don't think you are grasping it all on an intellectual level. We suggest going slowly, taking a little at a time, and doing the exercises or listening to the examples. If you have any specific questions about something you don't understand, don't hesitate to ask.