Not all U.S. Circuit Courts of Appeals (or federal district or bankruptcy courts for that matter) make full (or almost full) runs of their opinions available at their websites. See, e.g. the blog post at Gallagher Law Library (University of Washington Law Schools): Circuit Courts Archiving Cites to Online Sources.
The Administrative Office of the Courts is a one place to begin when researching federal court practice and procedure, but for cases, you need to do a little detective work if you want to use a free database.
The primary method for finding federal court case documents is PACER (registration required – some fees), but opinions from the Courts of Appeals, and other federal courts, may also appear elsewhere on the Internet. The AOC has links to federal courts.
Oregon Legal Research Blog

