Hello, Michael ---
I would start with the Grand Lodge of Colorado’s website (http://www.coloradofreemasons.org/default.aspx) they have a nicely laid out listing of Lodges by location in the state (http://www.coloradofreemasons.org/lodges/areaLodge.aspx) <including 3 Lodges that meet in Pueblo.> Keep in mind, many Masonic Lodges “go dark” (or do not meet) in July and August, so this may be a slow period for them, but keep the enthusiasm and interest and you will be rewarded if you join in the fall.
Best of luck, I joined “The Craft” when I was 31 and it has proved to be one of the best decisions I have made with my life.
Keep us posted on your progress!