Applications of 1H NMR spectroscopy - Proton structure elucidation written by P. Hallpap, H. Händel. Excellent work and very good for the beginner. - http://www.chem.uni-potsdam.de/~thomas/1hbuch/english/index.html
Proton NMR Tutorial - Tutorial and exercises on nuclear magnetic resonance. - http://www.wfu.edu/~ylwong/chem/nmr/h1/
Organic Structure Elucidation Workbook - A set of NMR stucture determination and assignment problems, easy, moderate and hard. (Select "problems" from left frame) - http://www.nd.edu/~smithgrp/structure/workbook.html
WebSpectra - Problems in NMR - More NMR practice problems and a great outline of spectral assignments methods. - http://www.chem.ucla.edu/~webspectra/