This requires a lot of detail to explain.
1. You need to callibrate your monitor with a hardware based tool such as from Gretag MacBeth.
2. Take a look at the turorials and articles here: http://www.computer-darkroom.com/home.htm
Ian has one specifically on printing with PS 7. He also has tutorials on calibration.
3. You may ultimately need to have a custom print profile made. Check out www.inkjetart.com
for a reasonably priced service and explanations.
4. You need to make sure that you are viewing the prints under the appropriate conditions - ie not a dimly lit room. A solux lamp is a reasonable light source.