Is it possible to use my usb bluetooth by connecting it to Arduino with USB A to USB B adapter? Any suggestions? Thank you very much.
Short answer: forget it. 
Longer answer: technically possible, but painful. If you have to ask then this isn't for you. This is the closest I've seen anyone get and publish about it. http://www.circuitsathome.com/mcu/programming/ps3-and-wiimote-game-controllers-on-the-arduino-host-shield-part-3
I have this on my to-do list. Keep putting it off because writing a slim verrsion of the HCI transport layer and then even slimmer Bluetooth HID profile on top, is just... well... not fun.
I have working Bluetooth "stack" - HCI, SDP, and RFCOMM. Hoping to get it released in a week or two, weather permitting.
Can you send me link when you release it? 