There's a special thing to be installed for it to cooperate in a mixed Vista XP setup. See the forum sticky.
PC with printer attached is Windows XP Home SP2. Running McAfee. Printers have "enable sharing" turned on (the little hand icon appears). Laptop is Vista Home Premium. Running Norton. When I tell the laptop to search for printers on the wireless network, it never finds them.
I should note that my previous laptop (Windows XP) never had an issue connecting to the same PC's same printers that I am trying to connect to now. Very strange. Is this a Vista -> XP issue? I have poked around in the McAfee setting and I don't see anything obviuos blocking the printer sharing. Also, as I mentioned, it worked fine with my old laptop, and I haven't touched the McAfee settings.