If you didn't sign and date your mailed return, the IRS will likely mail it back to the address on the return. In that case, you can sign it, date it, and mail it back to the IRS.
I usually use some kind of tracking when mailing to the IRS, such as Priority Mail or certified return receipt, so I won't wonder if they received it.
For a mailed return, it will not show up in their "Where's My Refund" tool until about 4 weeks after mailing. It can take approximately 6 weeks to get a Federal refund after a mailed return.
So after 4 weeks from when mailed (or when remailed if you didn't sign and date it), look for info here:
http://www.irs.gov/Refunds
TurboTax will continue to show "Ready to Mail" since it has no way of knowing if you actually did mail the return.
