On the topic of "why aren't there any good and simple web pages featuring RF math?", I found this one when Googling on the topic link budget calculation:
If anyone finds any other good RF math links then please post them to this thread.
antenna cable loss calculator
Vendor neutral third-party calculator
Cisco's Bridge and ROI calculators -
*Bridge calculator is on the right hand menu
Couldn't find Proxim's calculator ...
Hope this helps