is the referrer liable too

What is the name of your state? IL

Someone came to me for a side project. I am not incorporated but often do websites on the side for people. I could not do the project due to personal issues, so I referred this person to someone else. That person screwed up and now this client is threatening to take me to court because I was the referrer, will I be held liable also?

If you were not paid for the referral, no.