vrml editors: 
V-Realm Builder by Ligos Technology. A great VRML 2.0 tool for PC. 
Has a graphical display of the scene heirachy - which means you can create and edit small, efficient models. 

modellers: 
You will also need a 3D modeller to make more complex shapes. The modeller with the best vrml exporter is 3D Studio Max by Kinetix, which exports vrml primitives, all kinds of interpolators (animation), as well as an optimize function for polygon reduction. 3D Studio Max is expensive and has a steep learning curve, and should only be bought by those willing to spend 6 months learning it. Most other 3d modellers can be used and imported into vrml using a translator. 3D modellers tend to produce large vrml files with long download times. 

text editors: 
A good text editor is SitePad produced by ModelWorks Software. Very useful if you are to add scripts and such.