Rules Governing the Courts of the State of New Jersey, with comments and annotations by Sylvia B. Pressler. (Gann Law Books, annual editions), latest edition on two-hour reserve at the first-floor Circulation desk. Part III has the rules governing criminal practice.
The New Jersey court rules (unannotated) are also freely available on the Judiciary website, at http://www.judiciary.state.nj.us/rules/rules_toc.htm
Leonard N. Arnold, Criminal Practice and Procedure, 3rd ed. (West 1997) (New Jersey Practice series, volumes 31 & 32), NJREF room, call number KFN 1880.N4.
Kevin G. Byrnes, New Jersey Arrest, Search & Seizure: the Law of Police-Citizen Encounters (Gann Law Books), 2004-05 edition. Reserve, KFN 2376.5.N48
William D. Paton & Richard K. Hoefling, New Jersey Criminal Trial Manual (Hanford Publishing). Reserve, KFN 2375.A59 C74. A looseleaf digest of the caselaw, using quotations from opinions.