Printers

We have a domain w/ a NT 4 SP6 as the PDC. When we go to add printers and look at the browse for printers dialoge, some of the printers are listed at the top while most of the printers are under the name of the computer they are on. Why is this and how can we either make all the printers show up under the domain and not their computer or how can we remove the ones that are there?