Know how you feel, however I have the IP4000, bought last November 04, kept on thinking I had plenty of ink left in cartridges as always showing full. Thankfully though a yellow icon with a "!" inside showed up telling me that the ink was running low,this was about 6 weeks ago. I decided to buy a full set of inks from 7dayshop.com (very cheap site by the way for consumables) and one month later from intital alert am just starting to replace the cartridges.
My point, I would have thought the software you are running on the IP3000 is the same as the IP4000 therefore you should have had some warning!