It should have been in the same envelope with your tag or at least that is the way I use to get them when I applied for Elk. Last time I had a tag was 2003.
Regs are sent out with the deer and antelope tags because they are months after their completion. The elk Regs. are sent out in July separate from the early mailing of the tag itself because the Regs aren't finalized that early in the year.