i completely build and compiled code for displaying simple message in lcd. but unluckily i couldn't find lcdwindow like uart1 or other ports to display the message or required output. please help.
I think you would need to make a .dll to interface with the simulator if you want to simulate a lcd.
The appropriate app note for extending the simulator is http://www.keil.com/appnotes/docs/apnt_154.asp
normally, LCD interfaces, even if implemented in hardware (some LPCs have that feature) are nothing more than a simple serial bus. it is unlikely that what you need even exists. use your serial port while simulating.
Not true - see the App Note cited earlier by Nathan Duffy
Actually, this one would probably be better:
161: Interface and Simulation of an LCD Text Display http://www.keil.com/appnotes/docs/apnt_161.asp
The full list is here: http://www.keil.com/appnotes/list/uvision.htm
I stand corrected. Apologies, OP: I forgot about what Andy and Nathan suggested. I was thinking of an "out of the box" solution.