Before you can validate your app, it has to be Ready For Upload at iTunes Connect. When you submit your app at iTunes Connect, and you fill out the forms there with all that information, there is a final step that people often forget or don't notice; I have made this mistake myself several times. Until you do that final step, all your information for the app is there but you have not yet pressed the button that says you are ready to upload the binary. After you do that, you'll be able to validate or upload the binary.
For a picture of the button you have to press at iTunes Connect, see this answer: https://stackoverflow.com/a/13368431/341994