Anyone know of any examples on creating plug in's for VS2008 - preferably with VB.net?
If you can wait for VS2010, it should be lot easier because of new extensibility framework they use (MEF). Basically the extensibility hooks are now managed and are very decoupled.
Otherwise, I know this framework. I have never used it.
Or you can use the "Visual Studio Add-in" project template included in VS2008 ( File > New Project > Other project types > Extensibility > Visual Studio Add-in). It is hard to learn and debug, but it works.
Finally, if it is for internal use, you can just create simple VS macros that reference normal .Net assemblies. This is how I do internal extensibility projects because there is zero friction. You just create small macros that call your assemblies (to show a Windows Forms dialog for instance). Then you add that macro to VS toolbar or define a keyboard shortcut for it.
I hope this helps