Reddit reviews Hunting Wisdom: A Bacchic Orphic Diviner's Manual

Since you're asking this in r/HellenicPolytheism, I assume you're a Hellenic polytheist. If you don't have any other contact with the Norse religion, I would advise against runes - they are not just a divination tool, they are spirits as well, and deeply tied to the gods and cosmology of the Northern system; trying to separate them out misses a lot of the important understanding of them.

There are plenty of Hellenic systems: astragalomancy, bird augury, kleromancy, kledones, even necromancy. Some good books on the ancient traditions:

• Greek Divination by Halliday - available online here
  
• Ancient Greek Divination by Sarah Iles Johnston
  
• Mantike edited by Sarah Iles Johnston
  
• The Seer in Ancient Greece by Michael Flower
  
• Worlds Full of Signs by Kim Beerden
  
• And here's a simple Greek Alphabet Oracle that you can do with dice
  
  Also you might check out Hunting Wisdom: A Bacchic Orphic Diviner's Manual by H. Jeremiah Lewis, although it's specific to a certain Dionysian tradition, it also gives some great examples of how you can invent systems based on the ancient principles and tailored to your own religious needs.