PSO Health Care Deduction mistake

I filed my Fed and CA returns and had to pay both by check.  Both returns were accepted by the IRS and Calif and both checks have cleared.  I have since determined that I mistakenly answered "No" on the TurboTax Deluxe question if my income was from employment as a public safety officer when I should have answered "yes".  I am in fact a retired public safety officer and have received that deduction for several years.  The PSO deduction is in my case $3,000.  I know I have to file an amended return so that $3,000 needs to reduce my AGI which will reduce the tax I owed and result in a check back from both the IRS and Calif. How do I go about indicating that on my 1040-X amended return? Is there a charge by Turbo Tax to e-file my amended return to the IRS and Calif? Thanks in advance!