Is it possible to make soymilk without a "beany" taste?
The beany flavor is destroyed by heat. Some recipes do call for boiling the beans before grinding as you said. 

Most recipes that I have seen call for boiling the milk for a while after it has been strained. I find this more convenient as the milk is strained and pressed cold and then heated.

If your milk is still excessively beany then you may not be boiling it long enough to break down those indigestible compounds.

As for making it like commercial- most commercial soy milks contain a lot of extra ingredients to enhance the flavor and texture. Vanilla and sometimes sugar are added as well as calcium carbonate for creaminess, preservatives, etc. You can experiment with these if you would like but I found that I developed a taste for the flavor of fresh soy milk. It seems crisper and more naturally sweet to me than store bought.