Accseessing project assets from a custom editor

So i am working on a custom level editor for my game, that is a Unity Editor Script and not a runtime level editor.

Its basically just a row of buttons for easily creating the different level elements and a few useful functions like rotating and flipping objects.

My problem is how can i access the prefabs and button icons in my asset folder from a editor script? Preferably something where i can set up more buttons in the inspector, and not have to hard code each button.

You can access to any assets via AssetDatabase class. There are some methods to load assets: LoadAssetAtPath, LoadAllAssetsAtPath, etc.