Our frequencies are coordinated in Colorado by the Colorado Council of Amateur Radio Clubs (CCARC).
The Colorado 70cm band plan:
To my knowledge we have never discussed common Rising Sun 70cm frequencies. Nationally the simplex calling frequency is 446.000 MHz.
Finding other state's band plans, usually just Google but you can always hit up the ARRL and ask who's responsible for coordinating it. The group the ARRL recognizes as keeping tab on each state's responsible coordination body is the National Frequency Coordinators Council.
You have to scroll down, their jump to anchor tags are broken.