Here is a mirror of circos from http://circos.ca . Circos's author is Martin Krzywinski http://mkweb.bcgsc.ca/ .
- Google Group http://groups.google.com/group/circos-data-visualization
- stackoverflow http://stackoverflow.com/search?q=circos
And some Chinese community:
- 中文文档 https://github.com/node/circos-cn
- QQ群 ： 171307056
Circos is free software, licensed under GPL.