If someone is new and they ask a question that has already been addressed, I see nothing wrong with answering them the best that I can and then...
1.Explain that doing a search could prove beneficial for them.
2. I would also go above and beyond and explain how to do a search because if they are new.....they might not know.
3. Heck if you are really feeling helpful, do a search and post the links in the message.
I would do this because I have had years of customer service under my belt.