So I drew up some diagrams on paper, and then re-created those drawings in PageMaker. I know, not the best tool for doing construction drawings, but it was the best tool I had. This design drawing helped me figure out dimensions and from there, how much lumber I needed.
The first diagram (diagram 1) provides an overhead view of the bench top and the lower shelf. The lower shelf is set back so that you don't bang your shins on it and you can use a stool to sit at the bench. The second diagram (diagram 2) shows the lumber cut list. Not all of the pieces are shown, as some of them needed to be custom-cut once sections were assembled.
Hammerzone.com - Building a basic work bench
This work bench design was the primary inspiration for my bench. I made mine a lot larger and sturdier, but this article describes a simple work bench that can be built quickly, easily, and cheaply.
Popular Woodworking Magazine - $175 Workbench
This work bench design was way more than I needed, but the construction drawings and assembly instructions provided some good information that I incorporated into my design.
UniqueProjects.com - How to make a large worktable
This site has some good tips and instructions for building a basic work table. The recessed lower shelf on my bench was inspired by this design.
Boston.com - Solid core door work bench top
I had planned to use a solid core door for my bench top, but I wasn't sure if that was the best idea. This work bench design showed me that it would work fine, and gave me some ideas for attaching the top securely, without having any screws showing from the top.
Other Plans and Resources
Workbench Plans
Free Workbench Plans
Free Woodworking Plans - not just work benches