Find my printer's configuration web page

I'm trying to set the timeout on my Brother laser printer so that it winds down a minute after printing and doesn't sit there and whine for 15. I know I can do this through its internal web page. But what is its address? I tried looking in the printers control panel and in the CUPS system, but in both cases, the "Location" is empty... which is weird. AirPort Utility can't be bothered to list IPs. Anyone know how to find it?