if you're saying "The usbtiny is not connected to the Arduino or my Mac when I try to program via USB. Furthermore I know the USB port works as I can receive serial data in the Arduino environment.
I am running Arduino 0019 on OSX. I've made sure I have the latest FTDI drives."
that sounds like you're confusing the two
if you can program an AVR with avrdude, the programmer is working fine...you've probably messed up something with the IDE while experimenting. posting -precisely- what you're trying to do will be helpful. dont say 'program via USB' because that can mean many different things