Blocking Search Engine Access

Guys, I have this very big problem. I created this website from scratch and the amount of work that I have done on it is tremendous. However, I made the mistake of putting sponsor links at the footer page of my main home page. There is no way to undo this except trash out the website and make another one. I am afraid that when search engines especially Google crawls upon this, it will be seen as spam and I will be penalized. Is there a way to block search engine access to the footer part of my website? Please help me out guys!