H4 Visa for my Family( Wife & 8 months old Son) + LCA

I have H1B Visa Stamped in the last year (oct 2012). Due to some family problems I couldn’t able to travel till date.
Now, I have an opportunity to travel to a place which is different from the place mentioned in the petition.
I am planning to take my family ( Wife & 8 months old Son) along with me.
LCA is not initiated yet and will be initiated soon.

Here are the queries:
a. Which location ( Old or New) has to be mentioned while filling the DS-160 form for my Wife and Son.
b. Is getting H4 Visa independent of getting LCA for my Work?
c. Is my family members attend the H4 Visa interview only after I get the LCA.
d. Is there any problem to get H4 Visa by mentioning the Old location ( mentioned in original petition) before getting my LCA?

Please guide me on this.

At times, they ask for H-1 documents when appearing for H-4 interview. If they ask for 797, then its fine. However, if they ask for additional documents like client letter, project details etc and then do a background check, then it can be an issue; as that contract is no longer valid.

So my suggestion would be to talk to your H-1 attorney about it. Should she appear for H-4 stamping after LCA and H-1 amendment, or prior to that.