Beyond what others have said, it may take a fair amount of work.  I
just picked up a Brother 5460, and it took a solid day of hacking at
the Linux code to make it talk to the printer.  I'm trying to find
another day to figure out what I did, and -- with luck -- to turn it
into a package.

The problem is that my printer does not accept anything quasi-standard
like Postscript or HP-PCL.  There's a crazy mess of filters and the
like (with too much non-portable, Linux-specific code), but what it
ultimately resolved to was using gs to produce ppm and a Linux binary
to turn that into something the printer likes on its lpd port.  (Btw,
for the lpd option you need the queue name, and it took me quite a
while to figure out what that was -- and it wasn't anything I'd ever
have guessed...)