There are oracles since humanity wondered what the future would bring, or to help with decisions of the present. Simple ones and elaborate ones. The most simple one has survived the ages: tossing a coin. Or whatever is at hand, like pebbles or sticks. Everywhere one can find something, with which to solve the most difficult question of all: "yes or no"?
Another way is using your intuition. Because it has a way to hide, people found ways to trick it into appearing: eg by watching something random and accepting it as meaningful. The flight of birds - for the birds not random, probably, but often for us. Or the curls of smoke, moving water, dancing flames, the drabs in a cup of coffee or tea, numbers obtained in a random way.
The planets and stars in the sky are yet another way of foreseeing the future - or understanding more about the present.
Shen Shu by Zhuge Liang, an oracle of 384 poetic verses.
German translation by Stefan Kappstein, English translation by Yujing He.
In this website my own translation. In 2018 it will be available in print!
Geomantic tetragrams: an old European oracle of 16 four-line figures of single or double dots. It is like the Yijing, but very simple in comparison.
"Oude Europese voorspelkunst" by Karen Hamaker-Zondag.
The Ling Qi Jing, 125 verses by Tung Fang Shuo, Chang Liang, Huang-shih Kung or Liu An. Between 222 - 419 CE.
Two translations in English:
'Ling Ch'i Ching' by Ralph D Sawyer and Mei-chün Lee Sawyer,
and 'Spirit Tokens of the Ling Qi Jing' by Ivan Kashiwa.
Oracle of 81 four-line figures (tetragrams) with for each line three different possibilities: one, two or three parts. Each figure belongs to a period of 5 days.
Small part of the 5-page entry for this date.
The Yi Lin, Forest of Changes, has been written around 25 BCE by Jiao Shi (Jiao Yanshou) or Xu Jun. For every possible change from one hexagram into another it has a verse, usually of 4 x 4 characters.
It seems the 'change' is from the hexagram of the particular day, to the hexagram you cast on that day.
For the 'hexagram of the day' see HERE.