What I am saying is this. The affiliate link is resellerratings.com search which you can turn on or off in the admin options.
If your trying todo some other vendor then you would need to alter the code in showproduct.php for the dealtime link.
I cant really comment further as I dont know exactly what your doing. Now you can specify extra fields for products that you can call affiliate link and then put in a url but like I said it all depends what your doing so you will figure out how your going to do it.
If you know what your doing with php code its relatively simple otherwise you stick with filling out an extra field each product upload as in the paragraph above