Court rules control the conduct of court business. General procedural rules are usually statutory. They are uniform throughout an entire court system. More procedural rules, local rules, may vary among courts.

Federal Court Rules
The basic federal procedural rules are the Federal Rules of Civil Procedure, Federal Rules of Criminal Procedure, Federal Rules of Appellate Procedure, and Federal Rules of Evidence. These rules are printed in separate pamphlets, such as Federal Judicial Procedure and Rules, and also are included in annotated or unannotated texts of the United States Code. LexisNexis (genfed library, usrule file), Westlaw (us-rules database) and Bloomberg Law also contain the text of these rules. The rules of general application can be found on the U.S. Courts web pages.
Local court rules can be found in Federal Local Court Rules or West's state rules pamphlets (e.g. McKinney's New York Rules of Court, State, and Federal). They also appear on LexisNexis, Westlaw and Bloomberg Law in the various state rules files and on the Internet at the U.S. Courts rules site.
To locate federal cases that interpret rules, use USCA or USCS. For annotations to leading cases only use: Moore's Rules Pamphlets. To locate state cases which interpret federal rules use the various state Shepard's statutory citators. On Westlaw use KeyCite, and on LexisNexis use Shepards to find cases. Federal Rules Decisions contains District Court cases which interpret Fed. R. Civ. Proc. or Fed. R. Crim. Proc. and which are not printed in F. Supp. Secondary sources interpreting the rules (articles, speeches, and judicial conferences) are also included in F.R.D. F.R.D. appears in the frd databases on Westlaw. Two looseleaf services, with their own access tools, cover cases from all federal courts, including unpublished opinions. Federal Rules Service covers the Fed. R. Civ. Proc. and F.R. App. Proc. For the F.R. Evid. use Federal Rules of Evidence Service.
For explanations of the rules, consult treatises, such as Wright and Miller's Federal Practice and Procedure (on Westlaw as fpp) or Moore's Federal Practice (on LexisNexis as genfed;moores).
New York State Court Rules
New York state court rules are reproduced on the website of the New York State Unified Court System. Newly promulgated rules are announced also in the advance sheets of the New York Supplement and the New York State Register.
Official Compilation of Codes, Rules, and Regulations (NYCRR) volume 22 (parts A-D, "Judiciary") contains state court rules. Selected case annotations are located in part A behind an orange tab labeled Annotations - case notes and administrative notes.
The civil and criminal rules of procedure are included in the consolidated laws (Civil Practice Law and Rules in chapter 8; Criminal Procedure Law in chapter 11.) New York has a combination of statutory and common law rules of evidence. Many of the statutory rules are in articles 45 of the CPLR and 60 of the CPL. For annotations, use an annotated code set such as McKinney's or New York Consolidated Laws Service (CLS). McKinney's and CLS also include the text of acts governing various New York courts and the local rules promulgated by these courts. The ny-st-ann database on Westlaw and the ny library, nycode file on LexisNexis also contain the consolidated laws.
West publishes an annual pamphlet containing the rules of federal and state courts sitting in New York: McKinney's New York Rules of Court, State and Federal. Although not annotated, it contains cross references to annotated sources. The rules (with annotations) are also available in the ny-rules database on Westlaw and in the ny library, nyrule file on LexisNexis.
New York Standard Civil Practice Service, Desk Book (SCPS) is an annual one volume annotated guide to New York State court rules, including rules for specialized courts such as the Surrogate's Court.
The best source for local or individual judge's court rules is often the court's website.
To update state court rules by looking at interpretive cases, use Shepard's New York Statute Citations. The citator has separate sections for the N.Y.C.R.R. and the Consolidated Laws. Use KeyCite on Westlaw and Shepard's on LexisNexis to identify cases that may not be included in the annotated codes.