Hmm, I think that Nominatim gets updated with a bit of lag (minutes to an hour), so the address should be there now? Assuming you changed the information from the map, it should update it within Nominatim, as it get's it's info from the map

If not, you can leave a note http://www.openstreetmap.org/note/new and someone can take a look at it. I've been contributing for a while now and still like using Notes to let people with more techy experience or local knowledge help.