There are two general ways folk go about getting consistent colour between monitor and output.
As described previously in this thread the old fashioned methods of trial and error and 'mung and blur' are used by many. Monitors, printers and software settings are all juggled until some pleasing combination is hit on either with luck or with planning. It often works well for some images but fails for others, and if any variable in the chain varies then the whole process may need to be gone through again. What one saves on investment in calibration and charaterization hardware/software will often be spent in paper/ink/time.
The other approach is the more modern ICC approach, of calibration and characterization. There is considerable investment in learning and in getting hardware/software or using the services of consultants to produce output profiles, but in the long run this may be cheaper and more productive than the old hack methods.
Each device (monitor, scanner, printer) is calibrated to a known and repeatable state, which is ideally close to the optimum running condition for that device. When the device consistently performs at this level, it is then characterized (profiled).
A profile is produced for monitor, scanner/camera and output device/s. Then there is also the 'safe, neutral well behaved editing space' in use in Photoshop (presuming a ICC Photoshop workflow).
Photoshop knows how your monitor displays colour/tone via the monitor profile (created via eyeball or with accuracy via hardware and software). The input to Photoshop is described via a profile for the device which captured the data. A conversion takes place between the device space to the safe working space in Photoshop. Edits take place in this safe working space (such as sRGB or Adobe RGB). Softproof previews of output devices can be made while in this state. For output, the file is either duped and converted to print space or the working file is simply sent direct to the output device and Photoshop converts from the working space to the output device space 'on the fly'.
Try this link for more basic info on ICC methods and calibration and characterization:
http://members.ozemail.com.au/~binar...V_links.html#I
Hope this helps,
Stephen Marsh.