Simple download script

Project Description:
Need to write a simple download script.

1.download script look like: download.php?filename
Then the script will redirect user to the real download location

2.the script should find the file in a folder and its subfolder

3. the script should check whether a cookie is in the user browser before the download.

Additional Project Description:
04/04/2007 at 18:07 NZST
No need to do point 3. I have done it.

As for point 1 and 2, the script should search where is the real location of the file and then redirect the broswwer to that loation.