Hi, I'm trying to write a recommendation letter for an application using latex. My problem is (I've defined the document class as letter) the print area is rather small. I'd like the text to occupy more space in the page. How can I achieve this?
Thanks in advance.

You can use

\addtolength{\textwidth}{3cm}

or

\addtolength{\oddsidemargin}{-3cm}

and so on ....

I use package geometry (at the beginning of file):

just for extra general reference , below is a qoute directly from a LaTeX
tutorial :

.......
Readers from a word processing background are probably all thinking why there is so much white space surrounding the text. There is a good reason, and it's all down to readability. Have a look in a few books, and pick a few lines at random. Count the number of characters per line. I bet the average is about 66. Studies have shown that it's easier to read text when there are 60-70 characters per line - and it would seem that 66 is the optimal number. Therefore, the page margins are set to ensure that readability remains as good as possible. White space is often left in the inner margin for the assumption that the document will be bound, and so space must be allowed for this.
.......