The greatest accuracy would come from an expensive, high-quality display in controlled lighting conditions that has been calibrated using a calibration kit.
Only you can determine just how accurate you need it to be. With my photography I'm about halfway picky--good ACD, a little tweaking, but no calibration kit.
My school's newspaper has crappy 15" LCD panels that aren't calibrated, under highly variable viewing conditions. Same thing with the Yearbook. Sometimes, I can tell that's a problem (the printed product looks off). Most people don't see what I see (i.e. non-photographers don't care, and even some photographers truly don't see that their photos are off-color). And most of the time even I don't see any issues.
So, up to you. You can have the crappiest conditions and still usually get good results. Or you can shell out a few thousand for a setup and never worry about a discrepancy between a print and your screen.
MR has several threads on calibration. Peek around and you'll see them.