My FTA tv cable comes off a amplifier but there is only one cable, how do you connect to a FTA PVR? do I somehow have to make that one cable split into two by putting a connector on the end to be able to record shows on a PVR with the two tuners?

If you have a good/strong signal you won't have to, two tuner PVR's are able to loop the signal to the second tuner but it not you may have to.

I think most people are fine without a splitter.

For single tuner PVR's there is no need for two cables

I have a pretty good signal, antenna goes through the toppy's 2 tuners then to my LG HD STB then the last stop is the analog input on the plasma, I cant remember the last time I watched analog but no problems there either.

If you have a signal problem the first thing I would do it get a antenna guy out to check or replace the existing one.