If you used TurboTax last year then you can login and go to your Tax Timeline under My Account scroll down to 2015 and then expand the menu. There will be links there on how to download a copy of your Tax Transcript, which you would've had to use one of our paid products to get this feature; however, if you did then it will be on your transcript.
Alternatively you can also check any bank account information for around the time period that you believe you received the refund if you had it direct deposited. You also can get a transcript from the IRS by following this link.
https://www.irs.gov/individuals/get-transcript