Hi,
If you can afford a color PostScript printer, drivers shouldn't be an issue on almost any OS.
Failing that, you might check out [link|http://www.cs.wisc.edu/~ghost/doc/AFPL/index.htm|GhostScript]/GSView to see what printers they support. That would also eliminate almost any driver issues. (Ghostscript is a PostScript interpreter / rasterizer / converter that lets you print PS files to non-PS devices and much more.)
I've got an Epson Color Stylus 800 that I use with my OS/2 PC and my wife's Mac. It uses the IBM EpsonOmni driver. It's very slow in color under OS/2, but works fine with the Mac so it's worth keeping around. [link|http://www.os2voice.org/VNL/past_issues/VNL0200H/vnewsf5.htm|Here's] an old VOICE article on some of the various Epson drivers from 2000. (Note that I've never tried printing 32-bit color with it from OS/2 as my desktop runs at 256 colors.)
IBM's list of supported printers (by brand) is [link|http://www7.software.ibm.com/2bcprod.nsf/WebCat?OpenView&Start=1&Count=300&Expand=36#36|here] at the DDPak site.
Sorry I can't offer any more specific advice. Lexmark had a pretty good reputation when I kept up on their OS/2 support a couple of years ago.
A quick Google search turned up [link|http://www.os2world.com/os2usb/html/printers.html|this] page at OS2World. It talks about USB printers that are reported to work with OS/2.
HTH. Good luck!
Cheers,
Scott.