There are many references to the Garudas within the Buddhist Sutras. Most notably the Lotus Sutra and the Avatamsaka Sutra both refer to Kings of Garudas:


The Lotus Sutra

The Lotus Sutra in the beginning of the sutra speaks of the Four Garuda Kings, which represent the highest qualities of the ‘Wings of Speech’ which are dedicated to the Dharma’:

A. The Garuda King Greatness of Majestic Virtues representing all that which is temporary and provisional)
1. The Garuda King Greatness of Body representing emptiness
2. The Garuda King Greatness of Fulfillment representing the mean
3. The Garuda King As One Wishes, carrying the ‘Wish-Fulfilling’ (Cintamani) Gem around its throat, the magic gem that grants any wish to the one that possesses it. It represents the total blending of the three truths in a single thought.


Avatamsaka Sutra (Flower Ornament Sutra)


Volume 3, Section 3 (trans. Cleary)


Furthermore, the Garuda King Power of Great Swiftness had
found the door of Liberation of the non attached, unobstructed
eye observing everything in the worlds of sentient beings. The Garuda King unbreakable Jewel Topknot found the door of Liberation abiding in the realm of reality and teaching sentient beings. The Garuda King Pure Speed found the door of Liberation of the power of energy to perfect all means of transcendence. The Garuda King Non-Regressing Mind found the door of Liberation of bold power entering the realm of enlightenment. The Garuda King Steady Pure Light found the door of Liberation fully developing knowledge of the boundless differences in sentient beings. The Garuda King Beautifully Adorned Crown Topknot found the door of liberation adorning the citadel of the Buddha Teaching. The Garuda King Immediate Manifestation Everywhere found the door of Liberation perfecting the power of unbreakable equanimity. The Garuda King Ocean Surveyor found the door of Liberation knowing the physical forms of all sentient beings and manifesting forms for them. The Garuda King Dragon Sound Great Eye Energy found the door of Liberation of the knowledge entering into the acts of all sentient beings in death and life.

At that time the Garuda King Power of Great Swiftness, receiving the power of the Buddha, looked over all the Garudas and said in verse,

The Buddha Eye is vast and boundless,
Seeing all the lands in the ten directions.
Sentient beings therein are innumerable:
Showing great spiritual powers, he conquers them all.

The Buddhas Spiritual Powers are unhindered;
He sits under all the enlightenment trees in the ten directions
And expounds the truth like a cloud filling everywhere:
Jewel Topknot, hearing this, does not oppose.

The Buddha did various practices in the past,
Universally purifying great means of transcendence,
Giving offerings to all the enlightened:
This, the Swift King deeply believes.

In each pore of the Buddha
Boundless practices are shown in an instant;
Such is the realm of Buddhahood:
Adorned by Non Regression clearly sees all.

The Buddhas boundless wisdom light
Can destroy the net of ignorance and delusion
Saving all beings in all worlds:
This is the teaching held by Stable Light.

The citadel of truth is immense, endless;
Its gates are various and uncountable–
The Buddha, in the world, opens them wide:
Here, Beautiful Crown Topknot clearly enters.

All the Buddhas are one reality body–
True Suchness, equal, without distinctions;
The Buddha always abides through this power:
Immediate Manifestation Everywhere can fully expound this.

The Buddha in the past saved beings in all realms,
Shining Light throughout the world,
Teaching and taming by various means:
This supreme teaching Ocean Surveyor Realizes.

The Buddha sees all lands
All resting on the ocean of doing,
And rains the rain of truth on them all:
Dragon Sounds liberation is like this.