We present a brief atlas of L-band (3.3-4.2um) spectra for 42 stars plus the Sun and a sunspot observed at a resolving power of R~3000. This contribution is intended to supplement our previous K-band, H-band, and J-band spectral atlases. The L-band data, which cover some or all of the 2400 to 3000cm^-1^ (3.3-4.2um) region, are mainly for luminous late-type stars. In reducing these data, special care has been taken to remove telluric features, especially water vapor. We identify temperature- and luminosity-sensitive atomic and molecular indices to aid in the classification of stellar spectra in the L band.