Pretty much all modern wireless equipment is more than capable of doing a good job. When in doubt, go with an established brand like Linksys, Netgear, or Trendnet. But in general, anything that doesn't look obviously cheap will do the job.
I suggest to use the D-Link ones. Easy installation,good quality,and they don't break easly. Remeber,though,that there are USB,PCI,and PCI-MCA ones! The PCI and PCI-MCA (For Notebook) are the best.
Any wireless adapter will do, as long as they fit the network letter requirement of your router (wireless B, N, or G). Expect to pay between 20-30 dollars per adapter.
