How do I obtain my husbands SS number and address legally to file for child support since he won't give it to me himself?

You commonly can initiate the process even if you don't know all the rest of the person's information. You mainly need to get the court filing in then get the person served. If there's missing information, the court can require they provide it once the process is started.

That having been said, you commonly would not get support from a "husband." You get it only from someone to whom you're not married. So you may need to file for divorce first.

You need his name and last known address. Check with the post office to see if he left a forwarding address.

You cannot obtain his SSN from anywhere. You can have someone track him down to find an address.

Contact your local DA and their Department of Deadbeat dads.

That is, of course, if you have court ordered child support.

Hire a lawyer to get it for you.

Idk