Infrared absorption spectroscopy is a highly sensitive technique for probing molecular structure, and when combined with cold molecular beam methods it provides unparalleled spectral resolution and absorption sensitivity to transitions in isolated gas-phase molecules. A portion of this dissertation investigates molecular beams of large polyatomic molecules produced via laser ablation of solid targets inside a buffer-gas cooling cell. Using matrix isolation spectroscopy to study the ablation products of graphite, we observe carbon clusters C_3 to C_12 produced at a rate of approximately 10^11 – 10^12 molecules for every pulse of the ablation laser. In a similar fashion, we study the production of metal oxide molecules with a buffer-gas beam source by ablating pure metal in the presence of O_2 gas, and find consistent production of the WO molecule. Finally, we discuss efforts towards high resolution rotational-vibrational spectroscopy of WO in the gas phase.