Utilized Pegboards - Pegboards are a great tool that can be used almost anywhere in the home for organization. The same is true for your shed. For small tools, such as hand shovels and rakes, attach a pegboard to a wall and use various hooks and hangers to place hand tools and other items on. This gets them off the ground, out of the way and in a consistent spot that is easy to find.
If you want to go a step further and separate your tools, you'll need to get a bit more creative. One way is to utilize PVC pipe to make containers for your tools by attaching to two pieces of wood and hanging that from the wall. Another solution is to utilize a pegboard for your larger items as well, as they can hang from hooks similarly to smaller items.