Where can I find the payer ID number on the SSA 1099 form

Well there is no such thing  so if you think you need one then you are NOT entering it in the correct place in the program ...

To enter Social Security benefits reported on form SSA-1099

• Click on Federal Taxes (Personal using Home and Business)
• Click on Wages and Income (Personal Income using Home and Business)
• Click on I'll choose what I work on (if shown)
• Scroll down to Retirement Plans and Social Security
• On Social Security (SSA-1099, RRB-1099), click the start or update button

Or enter social security benefits in the Search box located in the upper right of the program screen.  Click on Jump to social security benefits