Your 1099R should arrive almost any time now--they typically arrive in late January/early February. It will come from the custodian of the retirement account.
You had tax withheld, just like you have tax withheld from a paycheck. The 1099R must be entered on your tax return, and TT will calculate your overall tax liability to show your tax due or refund. If this was a withdrawal before you turned 59 1/2 you have a 10% early withdrawal penalty in addition to ordinary income tax.
To enter your retirement income, Go to Federal> Wages and Income>Retirement Plans and Social Security>IRA 401 k) Pension Plan Withdrawals to enter your 1099R.