What does "airspace above 14,500 MSL is controlled with few exception" mean?
Class E airspace starts at 14500 feet MSL except for the airspace below 1500 feet AGL or designated and charted to start lower (SETVODA). There are areas like the US Rocky Mountains that are more than 13000 feet in elevation.

Class E is controlled airspace. Sectionals and charts will give you the information for the controlling agency. But just as if not more important, the minimum VFR weather requirements have to match those of controlled airspace (3-152, 5-111).

§71.71 Class E airspace.  
Class E Airspace consists of:  

(a) The airspace of the United States, including that
airspace overlying the waters within 12 nautical miles of the
coast of the 48 contiguous states and Alaska, extending
upward from 14,500 feet MSL up to, but not including 18,000
feet MSL, and the airspace above FL600, excluding—

(1) The Alaska peninsula west of longitude 160°00'00" W.; 
and
(2) The airspace below 1,500 feet above the surface of the earth.