North Carolina Tax Forms: http://www.dornc.com/forms/
Federal Tax Forms: http://www.irs.gov/formspubs/index.html
The library has a small selection of federal tax forms and workbooks in print format (1040, 1040A and 1040EZ); these are available to the general public. You can find them near the Reference Desk on the library's main floor. North Carolina forms are only available online.