What is the best place to look for historical variable star light curve data outside of the AAVSO database? I’m thinking particularly of stars that have type classifications in VSX (and so have obviously been studied to some extent) but have either no or very few observations in the database. Where can one find that data?
A place to start (not necessarily the end-all) is with SIMBAD, which is the astronomy bibliographic database:
…notice the tab to do search-by-name rather than by coordinates. This will give links to papers with (possible) data, but no lightcurves per se. For many types of stars, or individual targets you’ll have to build the published data into a file yourself.
It looks as though Geert Hoogeven’s scans of the historical ‘GuL’ are still available:
…which index the literature up to the 1950s.
FWIW, I have keyed-in large amounts (~100k lines) of photometry, mainly UBV photoelectric data, for relatively bright RR Lyraes and Cepheids. Ask me about specific stars (bas@lowell.edu). There’s also the Cepheid database by Doug Welch, which is no longer being added to:
All those should keep you off the streets for awhile.