You'll enter your donations for the year through the deductions and credits section of your federal return. Each non-cash donation requires a separate entry since your total non-cash donations exceed $500. If any of those donations exceed $5000 you may have to mail in your return along with signed letters from the charities that you donated to.
When you get to the deductions and credits section you'll scroll down to the charitable donations section. Enter each donation and all of the required information and the system will let you know what you need to do from there.
not entirely correct unless there's a glitch in Turbotax e-filing. you should still be able to file but use form 8453 to mail in the 8283 and related documents. following the instructions on the 8453 for submitting the form.