If you are serious about learning as much as you can about Wi-Fi, then look no further.
Certified Wireless Network Professional (CWNP) training is in my opinion the best wireless study material out there, and they are vendor neutral which means they only focus on 802.11 and not ‘how to configure with Vendor XYZ’. This is the first place you should go to start your Wi-Fi Journey of Knowledge.
They have the following certification programs:
In addition, I would recommend almost as equally the importance of utilizing the online wireless communities blogging and sharing of knowledge. Whenever I have trouble understanding a concept, I know I’m not the first, and I can always rely on the generosity of my peers. For a modest list of Wireless Experts, please see my Blogroll.