1. Does anyone know of any good tutorials for advanced modeling techinques?
2. Does anyone really like modeling in Houdini?
3. Does anyone know how to bring SolidWorks or Mechanical Desktop models to Houdini?
4. Does anyone know how to accurately model an object like a machine part in Houdini?

1) What do you mean by advanced?
2) Yeah, it's plenty of fun.
3) Houdini can read igs files.
4) It sounds like you're mostly intersted in modeling mechanical objects. For that type of work I prefer to use NURBS, and for NURBS I use Rhino. Houdini has them too, but I prefer Rhino because it is more robust in that department, since that's all it was designed to do, whereas Houdini does a million other things.

All of the “Advanced” modeling tutorials that I have seen have to do with creating people or faces. I am more interested in modeling up machines with exact precision. I currently use 3dStudio Max to generate 3 to 5 minute animations that show off different companies equipment for brochures or trade shows. I would like to move into Houdini because it looks like a better program overall, but I can't seem to get the model detail that I an looking for. I am sure that it is just a trainig issue on my part, but I would like to see some more tutorials based on machine modeling and animation.

Thanks for your response, I will take a look at Rhino.
I am looking for an animation software that has the modeling capabilities of SolidWorks or AutoCAD. It probably doesn't exist.

it might be worth reading through a few of these:
http://www.sidefx.com/community/learn/modeling/index.html [sidefx.com]
there are some there that may give you ideas on how to improve accuracy etc in your models