Not sure what is going on. I checked the two links on the homepage, for getting new posts, and both are working fine for me. Are you trying to get new post link from the top of the home page or the one on the left side of the page in the Site Navigation box, under Site Links?. Usually this stuff will be influenced by the cookies, the web browsers uses, so I would delete all your cookies, just in case it has become corrupted.
Here a link that should work with getting new posts, see if this works for you.
http://www.dobermantalk.com/search.php?do=getnew