Where might I find a free copy of my 2007 W2

They are always free, the place that you worked for, mails it to you.
Some furnish it online but they will notify you where and give you a passcode.

They are to supply ( mail it) to you by Jan 31, so you should be getting or have it by now. ** assuming they have your current address on file.
So call them up and ask them to send you one.