As for the 2017 tax file, search your entire computer system for any file ending in the *.tax2017 extension. Also look in the Recycle Bin. If you have multiple user accounts, also log into each one and do the search in each one.
The default location for TurboTax data files is \Documents\TurboTax folder (or for some \My Documents\TurboTax folder). But you might have saved it somewhere else.
If you use OneDrive or other cloud storage be sure to check those for the 2017 file as well.
Since you lost your 2017 CD, you can phone TurboTax Support and ask for a program download.
You can use the form at the link below to schedule a call back, or it may provide a number. Hours are 5AM-9PM Pacific (8AM-12 Midnight Eastern) 7 days/week.
Where the form asks what product you are using, be sure in the dropdown menu to indicate "CD/download" and the proper operating system, then indicate which Edition.
https://support.turbotax.intuit.com/contact