If you file a Form 1040, and itemize deductions on Schedule A, you have the option of claiming either state and local income taxes or state and local sales taxes. (You can't claim both.) If you saved your receipts throughout the year, you can add up the total amount of sales taxes you actually paid and claim that amount.
If you didn't save all your receipts, you can still choose to claim state and local sales taxes. You could fill out the worksheet and use the optional general sales tax tables in the Instructions for Schedules A & B (Form 1040) , but why not take the easy route and use the Sales Tax Deduction Calculator!
To figure the amount of optional general sales tax you are eligible to claim, just answer a few online questions and the system does the rest. First select the tax year for which you are preparing a return. Then, using your ZIP Code and just a few entries from your draft Form 1040, the Sales Tax Deduction Calculator will automatically figure the amount of state and local sales tax you can claim. You will see the results from your entries immediately on your computer screen. Even if your state and local sales tax rates changed during the year (e.g., because the rates changed or because you moved your personal residence), the Sales Tax Deduction Calculator can handle it.
This information can be found on the IRS website and is just one of many things you can find to help with any tax problem you may have. Another thing to do is look online using a search engine to find information and other resources.