Here is my Question: Where do I find the beetles?

well really myself i have never found one bu if you get 3 tech i exploration i think you can get beetles

the beetles are found once you clear out the brambles, around the area the brambles were.

brambles? Maybe you mean "Briar Thorns". you only need lvl2 exploration. Find the sharp object, the villager will take it to the research house-thing, now, all you need to do is place a villager on the thorns.