You can find the CP or LTR number on the right corner of the letter. Does anyone have sample letters to the IRS for different situations?Maybe one with code numbers and explainations. Most IRS letters and notices are about federal tax returns or tax accounts. Access IRS forms, instructions and publications in electronic and print media. We have provided sample letters that you can use to request waivers of several different types of IRS penalties. Refer to the tax return identified on the identity verification letter (Ohio IT 1040 or Ohio SD 100). See What is backup withholding, later. This Power Point is designed to walk our Ohio 4H Clubs and. Affiliates through the process of completing the online SS4 form to.