1. A guidance system, comprising: an ultrasound imaging device including a probe for ultrasonically imaging an image area including an internal body portion target; a needle including a magnetic element attached to a proximal portion thereof; a plurality of magnetic sensors included with the probe, each of the plurality of magnetic sensors configured to continuously sense a magnetic field of the magnetic element of the needle in order to generate magnetic field strength data; a processor configured to receive the magnetic field strength data sensed by the magnetic sensors to determine a position of the needle relative to the magnetic sensors in three spatial dimensions; and a display, wherein the guidance system is configured such that the display can depict the determined position of the needle together with an image of the internal body portion target provided by the ultrasound imaging device with the determined position and the image oriented such that an angle of the needle's approach to the internal body portion target is depicted when the needle is outside of the image area.