Once i get my us passport if i decide to visit india for 3 or 4 months with my us passport would i need a visa or i can just carry my us passport and travellet me know if any1 knows
You will need an Indian visa if you travel on your US passport.
well, there are 3 options to visit India if you are former Indian citizen:
1) Indian visa (business, visitor, student, etc)
2) OCI (Overseas Citizenship of India) - lifelong visa, not required to register at the police station in India forever.
3) PIO (Persons of Indian Origin) - valid for 15 years, required to register at the police station in India if stay in India for more than 180 days.
OCI vs PIO can be found at:
http://www.immihelp.com/nri/overseascitizenshipindia/
do u know how much it will cost me to get the visa and where can i get it
do u know how much it will cost me to get the visa and where can i get it n which one is better OCI or PIO
OCI treatment is same as PIO treatment but only differences are visa validation time, police requirement, and fees. In my opinion, OCI is better. OCI visa is valid forever (you don't need to renew it everytime.) PIO visa is valid for 15 years (it means you have to renew it every 15 years).
http://www.immihelp.com/nri/pio-vs-oci.html
http://triangledesi.com/2007/09/10/pio-vs-oci/
You will see the differences.
fees for OCI is $275 (refundable if rejected)
fees for PIO is not refundable (I don't know how much it cost).
Information about PIO and OCI is available on the website of embassy/consulate. I haven't applied for either OCI or PIO.
what about multiple entry visa 1 year multiple entry visa is also available would that work for me it says on the website Valid for six months to five years stay with multiple entry is given only to persons of Indian origini was born in india so i know i can apply for one but can i apply this visa for my 2 month old son also he is born us citizen