Keynote and Diagrams

I would like to create diagrams within my Keynote '09 presentations -- similar to the diagrams one can create in PowerPoint (e.g., flowcharts, models).

I can't seem to find "diagrams" within Keynote. I have been creating diagrams with objects, but it's becoming quite time consuming for large projects.

1. Is there a way to easily create diagrams within Keynote (other than utilizing objects)? It would seem like this would be a basic feature that is probably right in front of my eyes and I'm missing it!

2. If there is no way to create diagrams within Keynote, how do others work around this? Are there templates available online that can be utilized within the presentation?

Thank you so much for any help!
Carolyn