Large-format printing paper sizes in US/Canada?

For those of you in the United States and Canada, what large-format printing paper sizes do you have access to? There was a request for FreeSewing to add support for the 24" x 36" paper size. I was wondering if there might be different paper sizes we might want to add instead of or in addition to that one?

(And, for US/Canada folks who have places that print A0 patterns, do they actually print those patterns onto paper that is exactly 33.1" × 46.8", A0 sized paper? Or, do they instead print the AO pages onto 36" x 48", ARCH E sized paper?)