Blender 3D: Noob to Pro/2D, Toon, & CAD Rendering
|Applicable Blender version: 2.4x.|
2D, Toon, & CAD Rendering 
Rendering a 2D Black & White Line Drawing. (ver.2.49, defaults)
1) Background. Under the menu selections, "Shading" (F5) → "World buttons" → "World" tab. Turn the background (default is blue) color to white. The color selection box above the "HoR" slider.
2) Edges. Under the menu selections, "Scene" (F10)→ "Render buttons" → "Output" tab. Click the "Edge" button to turn on the edge lines. Adjust the "Edge Settings" if wish to change the edge intensity (sensitivity) & edge color. Under the "Format" tab of the same menu you can also choose to change the file format (default is Jpeg) & render size.
3) Object Color. Under the menu selections, "Shading" (F5)→ "Material buttons" → "Links and Pipeline" tab. Select the materials to be rendered. Once a material is selected, move to the "Material" tab and change the color (default is gray) to white as well. It is the top box of 3, next to the 'Col' button. Each material instance will need to be changed.
4) Shading. Eh, who needs it? Menu selections, "Shading" (F5)→ "Material buttons" → "Material" tab. Click on the "Shadeles" [sic] button to remove shading. Each material instance will need to be changed here as well.
5) Camera. Select the Camera in "Object Mode". Under the menu selection, "Editing" (F9) → "Camera" tab. Click on the "Orthographic" button, to flatten the image.
6) That's it folks. Hit F12 to render, and F3 to save your render.
*Note: Camera in Orthographic Mode:: Leaving the camera in Perspective mode will result in mesh lines being barely visible, almost white washed. Where as Orthographic mode will allow the mesh lines to become much more visible. And combining Orthographic mode with SubSurf, can help to create well defined curved surfaces. Just remember to change the camera lens scale, and Crease edges (Shift+E) where needed.
Edge Line Thickness
Overall edge line thickness can be changed by adjusting the render resolution. As such, the greater the render resolution, the thinner the edge lines will appear. Under the menu selections, "Scene" (F10)→ "Render buttons" → "Format" tab. Change the "SizeX" & "SizeY" entries (Max = 10,000x10,000). For complicated images at high resolution, you may wish to change the number of tiles rendered. Found under the "Render" tab, "Xparts:" & "Yparts" (Default = 8x8).
Edge Line Feathering
Edge line weight can be adjusted by changing the planar distance, in the 3rd dimension, of objects relative to each other. Or in other words, how close an edge is to a common plane or an angle to 180 degrees. Resulting in edge lines appearing lighter (gray) or even totally disappearing.
Some gradient can also be created in lines by sloping an edge towards a common plane. Causing lines to fade from black to white depending upon the relative angle.
What's Needed: A way of defining edges with line type, line weight, & color using blender. Any suggestions?
Putting CAD in the Blender
2D External Tutorials
2D Scripts & 3rd Party Programs