Forms for tax exempt, non-profit organizations are available on the IRS website. The website provides a list of federal forms by number that are in PDF format and can be printed, completed, and mailed. They include applications for recognition of exemption and forms that explain financial details to the IRS.
IRS.gov provides links to a long list of forms and instructions for tax exempt organizations, including charitable organizations, church and religious organizations, political organizations, and private foundations. Most of the forms can be printed and mailed, although Form 8871 and Form 990-N must be filed electronically, as the IRS explains.