Refrigerator Repair Experience?

I am somewhat of a do-it-yourself-er. I am having a ‘fridge problem. I am pretty sure I know what I need to do and I have Googled it, but I am curious if anyone has had this problem and what solution they used, outside of calling a repair person:

Water on the floor. Freezer is not defrosting. Makes a weird sound. My guess is that the tube to the drip pan is blocked. Any other sage advice? Any advice on how to clear a blocked tube?