I was past due several years on my property taxes. I am current now. How do I claim those amounts? An amendment for each tax year or combined total on current year?

you claim the deduction, excluding any interest and penalties in the year paid. For federal purposes when you itemize the deduction for taxes is limited to $10,000 assuming not filing  MFS). your itemized deductions in total must exceed your standard deduction to benefit. The exception would be if you are married filing separately and your spouse itemized. Then you must also itemize.