just search the web using "visio & isometric" You will get back a link to
a dude in Japan. He did a really great job on isometric shapes including
isometric fonts.
From a usage perspective, I modified them for shading, light source,
angle, and dimensions via custom properties (no vba). Took about 30 min
for the cube...took a day for the cylinder because there is not a real
nice way I found to add connection points on an elipse.
He really did a nice job with them.
Note, he does have some VBA stuff in some shapes of his stencil for things
like autofill but I dont use them because of security concerns.