The easiest way to find a printer that works in Linux (and Mac OS X)
is to find one that speaks PostScript. If the printer speaks
PostScript you're golden. You don't need drivers, just throw
PostScript at the printer and get output. You can add a  PPD
(Postscript Printer Definition) file to CUPS for the printer to easily
enable all of the printers features, but you can generally configure
the printers features through CUPS without a PPD as well. If you can't
find the printer's PPD file on the vendor's website it can usually be
extracted out of the Windows PostScript drivers. Having the PPD isn't
necessary in most cases.

For a network printer, just point CUPS to the IP as an LPR/LPD device.
Generally the URI looks like SOCKET://AAA.BBB.CCC.DDD:9100. Your
printer may support other options as well.

For B&W duplex printing I picked up a Lexmark E260dn a couple years
ago. It's been a solid little printer for the money, and Lexmark toner
cartridges include a return shipping label for sending the used
cartridge back to Lexmark. The only downside is it wasn't wireless,
but between mutiple Apple AirPorts and other routers capible of
running OpenWRT and other firmwares to setup wireless to wired bridges
this wasn't a concern.

I find the E260dn to be really nice for a laser printer for home use,
and no worries about properly disposing of used toner cartridges
thanks to Lexmark's recycling program. My wife beat the heck out of
the printer while working on her masters degree and the printer
powered through no problem. For occasional color use we have an InkJet
that we got free after rebate with my wife's MacBook. We rarely use it
for printing, mostly it gets used as a scanner and fax machine. For
pictures I take a USB stick to Target, or order through iPhoto,
Shutterfly, SnapFish, etc.

This may have changed with newer Dell printers, but one of the
drawbacks of Dell printers used to be that you had to order new
toner/ink from Dell as office supply stores didn't carry Dell
consumables. This can be irksome if your new cartridge doesn't arrive
before the old one runs out and you really need a hard copy of an
important document. :)


-- 
Andrew S. Zbikowski | http://andy.zibnet.us
IT Outhouse Blog Thing | http://www.itouthouse.com