theFork:
If you go to the receive tab, it should show a list of at least 5 unused addresses. Your used addresses get put into a collapsed list and you need to select the arrow that is pointing to the right to see those. Once you select that arrow, you should see all the addresses from your wallet.
Here's a screenshot of the arrow I'm talking about:
http://imgur.com/VdOpEp1If you can't see anything on the receive tab, that's a different problem. Could you post a screenshot of what you see? Please blur or black out any sensitive data.
Thanks