My wife filed for divorce in Santa Clara county California 8 years ago.

She, or you, must file in SD. Your attorney can file a proper motion to dismiss the SC case based upon lack of jurisdiction.

Is a contract allowing "balance billing" enforceable?

A contract to perform an illegal act is void as violating public policy.

Are my neighbors responsible for the damage to the fence on there sides .

If it is a property line fence, they are responsible. If it needs to be replaced, they will owe half.

Can you teach him to poop in the gutter?

A sketchy site on the dark web? Unbelievable! Not much chance of legal troube, but a higher probability of viruses.

What should I do if a YouTube Network is not paying me my rightful share of revenue from the ad revenue from my YouTube channel?

You have no agreement with them? You have no recourse except to complain about it and cross your fingers.

Not to mention copyright violation. ...

Sure, report the suspected child pornography to the FBI.

My facebook was hacked and I don't know who the hacker was but the hacker posted images of me naked asking for drug money.

I'd it is a crime, your first step is to take your evidence to the police and file a report. They will investigate, and if they find the perp,...

A seller agreed on a price, but I had a delay- after 6 months I finally contacted him but he doubled the price. Is this allowed?

Options? Renegotiate or forget the deal.