If you used the CD/Desktop version of Turbotax, then the only copy is on the computer where you prepared the return. Turbotax does not have a copy online.
If you used the Online version of Turbotax, See the following TurboTax support FAQ on accessing a PDF of a return completed using the online editions
https://ttlc.intuit.com/questions/1900748-how-do-i-get-a-copy-of-a-return-i-filed-in-turbotax-online
You can get a free transcript of your return from the IRS:
http://www.irs.gov/Individuals/Get-Transcript
You can get a complete copy from the IRS, but it costs money, see this link for how to get it:
http://www.irs.gov/taxtopics/tc156.html
