The old metadocs are at
UppIT! Free File Hosting just in case you wondered how to get the sym button to work, some kid stole and uploaded them :P
Metasequoia isn't as powerful as 3dsmax, but then again you can't run 3dsmax from a memory stick.
Don't worry about learning metasequoia so much as learning the techniques on modeling, as these techniques will transfer to other software.
I think the techniques you were originally referring to are 'box modeling', 'polygonal modeling', 'primitives modeling' and sometimes called 'low poly modeling', the google image search brings up some interesting stuff.
Don't forget to look at ready made models to see how they do the awkward bits, armpits are a nightmare, to me anyway.
One last thing, metasequoia has an awful rendering system, my modeling is done in metasequoia, the renders are done in 3dsmax, don't loose sleep because your models don't look as good as the ones you see on the net, even a box looks good with ambient occlusion rendering.
Have fun.