The concept of a guardian angel is not so different from the concept of a spirit guide, a power animal, the Norse concept of the other half of your soul, or similar aspects which are manifestations of the subconscious. At least from my point of view, this common thread would make a great deal of sense.
As with any other such entity born of your subconscious, it is possible to contact and work with them and learn from it of yourself and otherwise seek its aid. Many of the methods for contacting one's spirit guide might be used to contact one's guardian angel. In more formal practice, the first portions of the Book of Abramelin are specifically devoted to aiding you in contacting your Guardian Angel and seeking its assistance and wisdom.