2000 vw beetle , 2.0 . have lots of air coming into the reservoir after replacing the fan sensor. Fans work ok but water temp in res, is only 130F. Heater hoses are cool. No heat. Have no idea where the T stat is. Under the water pump or on drivers side of block where the upper hose is?

SOURCE: OVER HEATING

In the fan circuit...You have a temp switch screwed on the radiator, a fuze and a relay in the fuze box plus a fan.  Swap the relay with another relay, replace the fuze.  The other fan should come on when the a/c is turned on.  If you fix the fans and it still overheats, you may have a BLOWN HEAD GASKET.  ALSO ARE YOU BLEEDING THE AIR FROM THE SYSTEM?  DO YOU SMELL EXHAUST IN THE COOLANT?   

SOURCE: 1998 vw beetle over heating

that will the next thing.
make sure the water is restricted at any point, from the lower hose to the engine back to the upper hose and back to the radiator.
the best way to check that out is to flash the radiator. you can see the water change color and feel the engine temperture.

SOURCE: overheating problem

looks like you have done everything but the problem with your car is that the cylider head gasket has gone have a look at the dipstick or remove the oil filler cap if it looks like mayo then 100% head gasket has failed you said no water on the floor so it must have gone into engine only way this can happen is head gasket failing, if you have put lot of water in to the cooling system then your sump will be full of oil water mix.

let us know your findings so we can help you more if you need it

SOURCE: 02' VW Jetta GLS 2.0 Over Heating

Check the water pump... the impeller may be loose and the water/antifreze is not circulating.

SOURCE: top hose hot and bottom hose cool...replaced

sounds like your water pump is air bound ( there is a air bubble in your cooling system,or your water pump isn't turning.Bleed the cooling system by jacking car upso the antifreeze fill area is the highest point and run the engineat 1500 rpms add water if it goes down that tell you that the water pump is pulling.Also see if you have a air bleed on the cooling system.Keep the rpms up until you can't add anymore water then put cap back on before returning the engine to normal idle speed.