Where do I find a driver for using an HP Officejet 3830 using Sierra?

Hi GM3218, you can download it direct from HP's official website https://support.hp.com/us-en/drivers/selfservice/hp-officejet-3830-all-in-one-pr inter-series/7172321/model/7172322 or here http://printerdriversupport.com/hp-officejet-3830-driver-download/. Hope my answer can help you 🙂

You may not need to install anything if that printer is AirPrint capable. See Apple's description at this link.

Try HP's tech support site to see if they have a new driver or try using the El Capitan driver. This assumes that HP supports the printer on a Mac.

HP does not have a driver for that model for Sierra. It does have one for El Capitan at this site: HP OfficeJet 3830 All-in-One Printer.

You can try it and see if it'll work with Sierra. Otherwise you can try the open source print driver Gutenprint 5.2.11. It won't let you scan however. For scanning try using Image Capture and see if it will recognize the scanner. If not there's always VueScan. It has drivers for nearly every model scanner available.