You won’t find all of them at the post office and library. Instead, you can go right to the source online. View and download a large catalog of forms and publications at the Internal Revenue Service Web site or have them sent to you by mail. You can search for documents as far back as 1980 by number or by date.
The IRS also will refer you to a private Web site that lists state government sites where you can pick up state forms and publications.
By the way, TurboTax already includes all the forms you need, which takes the hassle out of deciding which forms to use. Just answer simple, plain-English questions, and TurboTax fills out all the right forms for you.