Keep in mind...the laws in every state are different.
1)Can I as the father block this by refusing to sign?
It depends on your custody agreement contained within the divorce. Do you have joint custody? Shared physical custody? Who can make the decisions on medical procedures...(like dental braces or elective surgery)you? your ex? Do you have to make them together? Who decides whether she goes to public or private school?
2)I'm sure tons of forms will have to be filled out to switch her name on legal documents such as SS card, bank documents, stocks, etc. Basically anything that has her sole name on it or an account that myself or another member of my family is the trustee for and my daughter being the beneficiary.
Tons of forms...not at all. It's a matter of filing a name change through your county court, then taking the approved form to whomever you want to change the name on a document. Her SSA number doesn't change and that's the real indentifier.
Does changing all these forms cost extra money besides the court fee my ex is paying to change our daughter's name? Probably not.
Any info will be greatly appreciated fellas and I will throw some nice bombs your way for it.
Seriously...what the hell do you care if your ex's maiden name is hyphenated to your last name. She wants family name continuity. I want all my daughters to retain my family name, too.