This is one of the best and most cost-effective CAN USB adapters on the market. CAN2USB is galvanically isolated and is available for purchase online.

  With CAN2USB you can monitor a CAN network, write a CAN program and communicate with industrial, medical, automotive or other CAN based device. The CANBUS USB adapter connects a CANbus to the USB port of a PC or notebook, which also supplies the power to the adapter (no power supply needed). 

  In the downloads section now you can find all the related drivers and software applications and even Windows 7 64-bit kernel driver, which was added recently.