you need to use the software I will tell you can solve your problem. it 's called "sou gou pin yin",find it and setup. you can see a Panel list when you want to type Chinese by it. you can find a small keyboard icon on the list,and kick right botton on it,and chose the No5 item,then you can see a small soft-keyboard. you will see the all Chinese "yunmu" with tone marks. good luck :D

for windows XP(vista maybe the same or alike): Control Panel->Regions & Languages->"Language" tab->press button"Detail"->press button"Add" choose "Chinese(PRC)" from the list check "Keyboard Layout/IME" choose "Microsoft Pinyin 2003" from the list press ok then it's done. use ALT+SHIFT to switch between languages CTRL+SHIFT to switch between IMEs

You can find pinyin tone charactor in MSpinyin input 2007 softkebord.in that way you can find the charator with tone marks .