How do you let someone down kindly and gently?

I have been speaking to this bloke on the mobile for three days now and he keeps insisting he wants to come and meet me although he knows nothing about me and we have never met. I have been getting constant calls saying how lonely he is and how he cannot wait to meet. He has finally after much persuasion sent a photo and I cannot stand the sight of the picture, he is not my type at all! How can I tell him not to come without hurting him? There is just no chance for him. Shall I lie and say I have someone else?