By Business English, cover letter

We are artists/painters, with no funds and we are expecting to have a many more artists in our organization. So we want to write a letter to the different companies asking for a sponsors/support. I need your help on how to write such a letter or please send me a sample of a sponsorship...

It is me again. I am sorry but the format that appears inthe web is very strange. I do not want to complicate the correction, so I post it again. Hello! I keep writting cover letters... In every case I have to modify some things depending on the job, but I use the other corrections I have...