Ok this is really vague. What type of Software Archtect are you looking for? What focus? What type of applications?
Try this simple search string. I eliminated non-resume results and limited to the area codes of Silicon Valley. I could have also added some city names (San Jose, Mountain View etc...)
resume objective 408 OR 650 "software architect" -submit -your -apply -job -jobs -sample -eoe
As far as returning to India, do they have to be based in Silicon Valley? I would reach out to the Alumni organizations of Indian schools or the Network of Indian Professionals (I think selling working in India would be easier for someone from India)