Find someone who works at firm A and ask for one.

i did speak with someone at firm a.

firm a employee: "you know that's illegal right."

looked up firm A's website...it's all there...extensions and everything. 1300 names.

So how do I get firm B's directory if it hasn't one on their site...legally?

If it is in fact illegal where you are, why on earth would you commit a crime just to prospect?  I’m not trying to be critical, but that doesn’t cast you in a very favorable light. 

You think assuming I would casts you in a better spotlight?

I never said I was. I didn't ask this person I am very close with to even bother.

Do you make it a habit making curious people out to be criminals?

Yeah, you're right.

Good luck.

err..i am so sleepy. that first line doesn't even make sense

Ask a second person at firm a.