I see no reason why CentOS can't run wireless, but another similar distro might be better. CentOS is more dedicated to servers. It usually likes getting stuff through Ethernet. There are powerline Ethernet adapters like these which will let you go wired instead of wireless.
Although you haven't asked, typically when running a printer CentOS will prefer a networked printer which understands RAW files as opposed to one that plugs in with a USB. YMMV.
Go to Amazon and search for Ethernet over power.
Of course, you can also share an Ethernet connection from a second computer but that's doing it the hard way.
Have you considered Fedora or Fuduntu?
In any event, the first step is to rule out hardware issues. Make some bootable DVDs or live USBs with a distro other then CentOS. See if they can use the wireless and if so, how well?
If stability is a concern with Fedora, use the second most recent stable version not the newest one. You will still have to add all the codecs. Use Google to find the Wiki article on livna. The link sometimes changes.
There is also another good networking utility called Wicd which works on many different Linux distros including Fedora. The RPM file for that may run on CentOS as well.