urgent doubt on umlaut (Frankfurt)

Hi
I hope this doesnt sound too silly but i have been trying to break my head on this for quite some time now, how does one use the Key Board(laptop Compaq doesnt have a seperate numerical pad) to generate the Umlaut character? I am finding it too painful to keep on copy paste from a text file especially when ich mo:chte !(i use it almost for everything nowdays)

Cheers
Venkat

sorry if it is a stupid doubt and in the wrong forum! but shows how desperately i have been searching for something like this!