Tecnologi-ovedì: Typing Accent Marks
On a PC:
You can change your keyboard by following the directions here.
You can open the Character Map and copy/paste it.
You can try the method using ALT + numbers typed on the number pad, which doesn't really work if you have a portable computer.
In Microsoft:
You can choose Insert->Special Character.
In Word, you can click the ALT button & the accent mark followed by the letter it is to appear above.
In OpenOffice:
You can create a Macro following the instructions here.
On a Mac
You click OPTION(in the old days this was Open Apple) & the accent mark followed by the letter it is to appear above.
But, I've saved the best, most universal one, least daunting one, for last:
It's called Typeit.
It helps you type symbols, currencies, IPA symbols, and accent & diactrical marks for more than 20 languages. Just type it all in the box, select, copy and paste!