Network help!!

This is really starting to **** me off. I have a good sized network and the other day I had some problems with it...I thought I had them fixed becuase now every machine on the network can see all the others (via ping), even my iBook. However, all the other computer can also use the internet i.e. webbrowsing at the appropriate speed, but my iBook can't seem to find any websites!

It is really starting to **** me off and I can't figure out why this would happen. Any clues?

Are you not able to pull up any websites, or are the webpages you are trying to visit just loading slowly? Which browser are you using?