DATA TRANSFER THROUGH WI-FI

We need help for our Project
We are making some hvac control system and one aspect is to use different sensors like moisture, temperature , air pressure and air flow and getting the data back from these sensors thru wireless connection using arduino yun . so the data is suppose to be transferred from the sensors to the arduino yun then wirelessly transferred to the routuer/server and wirelessly into our computer however we are struck and couldnt or dont know how to get the data back from the arduino yun . we are very new to this and have been going thru the sik getting started book and searching online for hints on it and tried it out multiple times but it didnt work. this is just a small part of our project and we have been stuck 3 weeks figuring how to type the code to get the data bak. can someone tell us a code where we can get the temperature sensor to sense temperature and send the data bak wirelessy without any connection between the laptop and arduino yun? of course we would also like some explanation on how it works so that we arent blindly copying , thanks (: