You can get wire mesh baskets in a tier of three graduated sizes for small items, or use plastic hanging pots for other things, or if you make a 3-way hanger of brightly colored cord, almost any lightweight plastic basket etc. Think of all the colors available. I think, just much more practical. Another great project for summer. Now get some storage boxes, cubes etc. to store the rest of your stuff.
Underbed boxes help too.
If the shelves are real full of stuff, make some covers to hid the contents. Think Lynette Jennings on Discovery Channel has done them too. Your library may have some books on kids rooms that you could look at pictures for ideas. You don't have to copy exactly, just ideas and make it your room. I like the idea above about a loft.