Calibre does not recognize Kindle Fire HD on Mac Leopard

Calibre recognizes my Kindle DX, and Kindle Keyboard, but it does not recognize my Kindle Fire HD. Help please. I really want to be able to plus in USB because my library is large. I was emailing to Kindle but I would prefer not doing that.

I am considering a Kindle Paperwhite. Does Calibre and Mac Leopard recognize the Paperwhite? If Calibre doesn't recognize that either I will not get it.

Again I have the latest Calibre and it is on Apple Mac Leopard computer.

Thank you.