Neptune will be turning retrograde in the ninth house on June 7 and will again station direct on November 13, 2013 (keep in mind that two other planets are also currently retrograde, Pluto retrograde and Saturn retrograde).
Though Neptune retrograde energy is not that much more noticeable than Neptune energy when direct (due to the fact that it spends about 40% of the time in retrograde motion), you can expect to feel much more in tune with the unseen world, as Neptune governs the hidden. Your sixth sense or imagination could be heightened. You may feel more spiritual, or more connected to your spiritual beliefs. Expect ninth house themes of philosophy and ethics to be especially of note. However, because Neptune is also associated with confusion and deception, you may also feel more suspicious of those around you (or their actions and intentions) during this period of retrograde motion.