Yes, you can rent tuktuk from Lee Garden to the floating market (I just came back from there last week). But apparently, very few tuktuks come BACK into Hat Yai city, so the hotel staff advised me to book the tuktuk (this will cost about RM50, which is in my opinion, a bit too high), so the same tuktuk will wait for you until you are done eating and shopping, and take you back to the hotel.