Because the Akashic Records are a non-physical plane of existence accessible through spiritual means such as meditation, dreams, or honed psychic abilities, they don’t “come from” anywhere per se. 

My first knowledge of them was from A.R.E. where mystic Edgar Cayce explained that every action, thought, desire or deed creates a vibration that marks the thread of space and time and is permanently associated with the individual (soul) responsible. 

Since they are considered a “metaphysical concept” that suggests the Akashic Records as a source of information as an ethereal library containing the collective knowledge and experiences of all beings throughout time… think of them as the energetic place where all knowledge and experiences lie. 

That would mean they come from knowledge and experiences throughout time.