We already compiled quite a bit of information from PCMDI in these documents, which contains many useful links:
We have also downloaded portions of various observational and reanalysis datasets including ERA5, ERA-Interim, MERRA2, NARR, ana4mip, esg_obs4mips, obs-CFMIP, and obs4mips.
Sharing scripts to perform common functions (e.g., for generating climatologies, regridding, making plots) between participants will be a great benefit from this coordinated activity. If you have ideas how to facilitate this, we would like to hear from you. A range of ideas have been mentioned (from a simple directory where everyone can copy scripts to a github repository); but requirements from the contributors would be different (documentation, etc.). Let us know if you are interested in coordinating this aspect of the activity.