Plant metabolomics has benefited from a rich array of pre-existing methodological approaches and bioanalytical knowledge for the characterization of the many chemically diverse classes of metabolites. While the field has pushed the implementation of unbiased and generally applicable strategies for metabolite extraction, fractionation and detection, significant challenges in fundamental activities such as compound identification and quantification still exist. This review provides an introduction to metabolomics terminology, methods and resources and discusses analytical limitations. Progress in the application of stable isotope dilution and stable isotopic metabolic labeling to metabolite identification and quantification are discussed. New strategies to address spatial distribution of metabolites via mass spectrometry-based imaging are also reviewed.