Tabulated absorption spectra of greenhouse gases?
Contributing to the first half of the answer: The MPI-Mainz UV/VIS Spectral Atlas of Gaseous Molecules of Atmospheric Interest (public access here) allows you to search by chemical name, sum formula, CAS registry number, InChi key or author.

The output is a plot, annotated with the literature reference, e.g.



(reference)

It does not cover IR data to cover the second half of your question.  However, why not asking them if they in turn would know about a complementary database and letting the users of ChemSE know about their answer?

(Otherwise, if affilated with a research institution with a department of chemistry, knowing a chemical identifier like the CAS RN could help you to retrieve spectral data in Elsevier's Reaxys [rooted in Beilstein and Gmelin database], too.)