Need Help With Blog Redirect Codes

I need help with redirect codes. I want to use one blog, and be able to redirect my email subscribers through that blog, and directly to several different affiliate offers. I am trying to eliminate the long ugly affiliate links, that scream, I'm trying to sell you something, from the emails I send out on a variety of subjects, with different offers.

I bought a neutral domain, and I can put a product related phrase after it like getmoreinfo.com/lose-weight

I have managed to figure out how to get the home page of the blog to redirect to an affiliate product, by inserting my redirect code into the index.php file.

My question is how to I get other pages to redirect to affiliate products. I made a second page on this blog, and I have poked around using my ftp program, and can't seem to find where I would put the redirect code, to make it redirect to a different affiliate program.

I have a hostgator reseller account. I do see another index.php file in the wp-content folder, but I am not sure if that is the place.

This is the redirect code I am using
<?php
header( 'Location: http://myaffiliate.productid.hop.clickbank.net/?tid=18' ) ;
?>

Thanks Glenn