How can I automatically output it to pizza or bar graph,
using only the native VFP9 tools ?

You can use MsChart.ocx: one of the activeX controls that ships with VFP.

You can also download the white paper and code samples from my conference session entitled "Creating Graphs With VFP". You will find it on the tools and utilities page of my website. There is an example in there of how to use MsChart.