formal letter writing

[gan]

suppose i wish to write a formal letter. a complaint letter, what is the commonly used sentences? is there any useful guidelines?

[Casiopea]

Welcome, gan.

Here are two sites that may interest you:

http://www.businessballs.com/complaintsletters.htm
<There are sample letters at the bottom of the page>

http://www.howtocomplain.com/info/cl-template.shtml
<At this site, you enter the info and a letter is automatically generated>

Hope those help.