If you are a new Assesse go through the relevant links to find your Assessing Officer (AO) and Range/Circle/Ward. You can also go through the Organisation Structure to get their Jurisdiction details and addresses.
One can find their assessing officer using the following link
http://www.incometaxbangalore.org/jurisdiction/jurisdiction.htm
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How to know the ward/circle while filing of income tax return for mumbai region
this should help https://incometaxindiaefiling.gov.in/portal/common.do?screen=jurisdiction