1. Try to do a Freedom of Information Act Request on form G-639 (http://www.uscis.gov/g-639) - you might be able to get a copy of both the I-140 and the Labor Certification. Note that it does not work all the time. The Shah Peerally Law Group PC has been successful in few such cases. You can reach us at 510 7425887, if you need any help; or
2. If you have the receipt number mention the receipt number and print the online status from www.uscis.gov.
3. To obtain a copy of your labor certification for other purposes you can refer to our forum for guidance http://www.splawforum.com/threads/45-Obtaining-your-Labor-Certification-copy-through-FOIA