The Minecraft Coder Pack contains Minecraft code that can be copied into your mod and modified to suit your objectives. It is an invaluable learning tool as well.
Blocks don’t have to be cubes. Creating a non-cubic block is tricky but Mr. Crayfish has created a program to help simplify making the block model simply called “Model Creator“.
The Minecraft ID List provides basic information about all of the vanilla blocks and items in Minecraft. A tip of the hat to Graham Edgecombe for providing this useful information.