need to chat/email/talk with adobe support about billing. How can I contact them

Chat support: https://helpx.adobe.com/contact.html?rghtup=autoOpen
(type "Agent" to chat with a real person)
Phone support: https://helpx.adobe.com/contact/phone.html
There's no email support.

Beware of people contacting you via the forums' messaging system pretending to work for Adobe! Only those with an "Adobe Employee" tag under their name are legit. Also, Adobe will never offer to contact you via Skype, or use an email account that's not under the adobe.com domain...