There are many ways to achieve this:
1. You can use third party dlls to create charts, many are available in market, if you are lucky u will get something free.
2. You can use System.Drawing.Graphics in .net to create your own charts (I assume your requirement is very basic). Its should not take long.
3. You can use CSS, simple bar chart can be created purely using CSS, for pie chart you can use different images and show them based on calcuation. for example you can have 20 odd images(pie01.gif, pie02.gif...) and based on calculation set Style Image to relevant image. for 20% useabge set image = pie02.gif
Its the cheapest and fastest way to achieve this.