i use PrinterShare that i got as the amazon free app of the day like a year and a half ago. costs $15 now, though.
i remember seeing MotoPrint on my phone before JB, but i have no idea if it's compatible with JB since google removed a lot of the moto bloatware with the JB update. i've never used it, so couldn't tell you if it's good, or anything else about it.