.htaccess file took my site offline

I seem to be having some trouble with this.
First I haven't found the code that you put on each page in the location you want the ads to appear.
Secondly, the .htaccess file....
Do I create it in notepad? Or an empty html template?

well....where do you type that command?

thanks

 

i tried using this as my .htaccess

but my site won't load...

following the directions on this thread....http://forums.digitalpoint.com/showthread.php?t=5659&highlight=htaccess
doesn't seem to work because they don't reference the _250 version.

help?