If you used the desktop CD/Download editions installed on your computer, the only copy of your tax data file and any PDF's will be on the computer where the return was created. TurboTax does not store online any returns completed using the desktop editions.
NONE of the Downloaded versions will do that ... they are never stored online with the Online versions ... they are only stored on the computer you use or any other storage medium you used. It is your responsibility to save and safeguard that info.
Yes. My DocsTM not only lets you upload and store up to 100 MB of your own tax documents (scanned receipts, W-2s, and things like that), it also stores all the TurboTax Online returns filed using that account.