When you first go to the W-2 topic, is it showing you an employer that transferred in from last year? Is there no option to skip that particular W-2 for now? For instance, is there a button somewhere below it that says "Add another W-2"? If that button is there, then go ahead and click to add the W-2 that you DO have. Later after you receive it, you can go back and provide the info on the W-2 you haven't received yet.
If there's no way to get by it, another possibility would be to skip through the screens for that unreceived W-2, and at the end of that W-2, you can click on "Add another W-2" to enter the other W-2 that you DO have. Then later when you do get that W-2 you skipped through, you can then go back to the W-2 section and choose "EDIT" by the skipped job to provide the info.
And, of course, as xmasbaby0 cautioned above, do NOT efile anything until you have ALL of your information entered and finish your return.
