If you want to send the pictures to the lab to be printed, then the output profile, be it with paper simulation or without will be needed, on top of a calibrated monitor. Of course not to mention physical calibration prints from your LAB for comparison and fine tuning purposes.
so far i have only used the Gretag Macbeth's EYE ONE, EFI's ES1000 and Heidelberg's Print open to create output and simulation profiles for offset and digital print; also for monitor calibration. My personal view is that you
MAY be able to skip the monitor calibration part, if you know what to do ; i.e playing with ADOBE gamma or the knoll software(which is very old and outdated, but works wonders!!!!)
One thing to take note though, all labs have/uses consumables, thus sometimes you will find that your colour prints "drift" a bit from the desired output(from what you see)
hope that helped.
cheers