Thanks for your explanation and I apologize for probably my not friendly post. I am under pressure to finish this job. Thank you for understanding.
Finally after hours of search and effort I could create a table with 1773 cities (CA) with their relative tax rates. I created 3 columns in this table,TaxID,City and Tax columns.
Now I need your help and assistance to go from there please.
Should I add more column to this table? If yes, please mention which one and what to assign in Type in phpMyAdmin.
Should I remove tax setup in PayPal (I've already set it up to 9.75%) and let eCart do the job?