Probable Clogged Defrost drain tube

Water is accumulating under the vegetable pans of my fridge and I have been told that I need a specialist to come fix it. I am trying to avoid that so does someone know where the tube is located and how to do it and/or give me their insights on the problem? If I have no other choice than to call a service specialist I may consider buying a new fridge as mine is more than 5 years old and since you never know how much you are going to be charged for the repair (could be in the $200 range)it might be more advantageous to just buy a new one.

Thank you for any help.