I love Toodledo, but, full disclosure, my system is on paper right now, since I show it to people when I'm training, and they "get" paper much more easily at first.
Toodledo works best when you keep it simple!
I created folders for:
Each project, action item, etc. was a task, filed in the appropriate folder.
The only tags I used were for action items, to indicate context (@home, @phone, etc).
I used the task's note field for support information or to note where my support was located, but only if I really needed it. You don't want to spend 5 minutes entering each item!
Here's an example:
Task: "Build Widget" with a note that my widget specifications were in a project support file at the office.
Task: "Send copy of widget specs to engineering" Tag: @Office
I didn't use the due date or alarm functions in toodledo - if something had a particular due date, I noted it as part of the task name, then on my calendar as a day-specific item, since I look at my calendar more frequently than my lists throughout the day.
If something was really "hot", I used the star.
The fewer fields you use in toodledo, the easier it will be to use your system quickly, especially from your phone. You want to pass the "flu" test. If it's too complicated to use when you are feeling your worst, it's just too complicated!
Toodledo also offers a basic notebook. That's where I kept GTD-related notes, such as my "Horizons of Focus" lists. I only looked at those during my Weekly Reviews, so I kept them separate from my folders so I wouldn't have to look at them more than I had to. Evernote is a much better product for storing and searching for reference and project support items, and it's free
All the best,