If the IRS owes you money, they don't care how late you are. If you owe them money, then they charge a penalty for being late.
You can attempt to e-file the federal or just print and mail again. Pay careful attention to the cover sheet that prints out with your return. It will tell you what documents to include and the address to mail the return to.
Make sure that you sign the return in ink before mailing it. Also take it to the post office and send it so that you get notification when it is delivered to the IRS. Keep that with your tax records.
