This is the official site for the State of Colorado government. From here you can access tax information or contact your local government agency. This web site will contain links to all 63 counties web sites.
Some counties however have yet to create a web presence.
This is a link to all the current and archived statistical information you will ever need for the Denver metropolitan area. This site is maintained by the Denver Public Library. Microsoft Home Adviser Microsoft has a neat site that organizes loan, school and neighborhood demographics for any area in the USA you are researching. This link will take you to the web site for the Colorado Department of Education. From this web site, you can explore information from all schools and districts within Colorado.