These are simple CSV files matching counties and ZIP code tabulation areas to their geographic centroids. While I would prefer a programmatic process, here's how I've been doing it:
- Download the SHP file from TIGER
- Open that SHP file in QGIS
- Exporting the vector as a CSV, which converts just the data portion.
These files all have both a GEOID10 column for the county or ZCTA and two rightmost fields: INTPTLAT10 and INTPTLON10
Please feel free to suggest other geographic types of (better yet!) send me PRs.