OK, I got a turn around solution.
I installed two shipping methods from add on modules as suggested by Ajeh.
Seven-Zone Zipcode-based shipping module and zone table.
I faced issue with zipcode addon as the table name was changed, but I changed the table name to zen_zipcodezone in the database.
So, now I have a free shipping for the city in which the store is located specified in zip code shipping module and rates as per weight for all other state/zones as specified in zone table shipping module.
Some minor hiccups are there, but are acceptable to start with.
Thanks,



