Oklahoma Legislature: http://www.oklegislature.gov/
Search for pending legislation using the Bill Number by entering the number and clicking search. Advanced Search can be used to search bills from a prior legislative session.
Find municipal law-related legislation using Westlaw: From the homescreen, go to "Practice Areas" then "Municipal Law" then "Municipal Law Statutes & Court Rules." From there, you can narrow by jurisdiction and search.
Search current legislation using Westlaw: From the homescreen, go to "Practice Areas" then "Municipal Law" then "Municipal Law Proposed & Enacted Legislation." You can search the jurisdiction and year to see enacted legislation. For example, searching "Oklahoma 2015" returns 25 results for enacted legislation in 2015.
Pending legislation is legislation that has been passed through the legislature and signed by the governor but has not yet come into effect. Information on pending legislation that impacts municipalities can be found on the Oklahoma Municipal League's (OML) website.