If you were expecting to receive a Form 1099-R, but haven't received it, you should contact the payer to request a copy of the document. You will need the form in order to complete your return.
Income reported on 1099-B "Proceeds From Broker and Barter Exchange Transactions" is reported as Investment Income. To access this section of your return, type "1099-b" into the search box, and click the "Jump to 1099-b" link. Follow the program prompts to complete your entry.