The journal Concepts in NMR (Wiley) provides didactic articles on many aspects of NMR spectroscopy. Methods in Enzymology 176, 177 (1989) and 239 (1994) have many useful articles on deuteration and other isotope labeling methods, sample preparation, assignment methods, instrumental methods, distance geometry, molecular dynamics studies and simulations, phosphorus NMR, ligand binding, exchange effects, in vivo enzyme activity measurements, multiple quantum methods, total correlation spectroscopy (TOCSY), rotating frame Overhauser effect spectroscopy (ROESY), nuclear Overhauser effect spectroscopy (NOESY) and COSY.