I'm trying to find a report of federal early childhood education funding levels by state, by year. Any ideas?
ED.gov's State Fact Sheets on Proposed Federal Funding for Preschool for All is the report you are seeking. These reports are all about "Increasing Access to High-Quality Early Childhood Education", divided by state, and include federal funding data:
Head Start Program datasets provide annual information on demographics, state allocations, program statistics, and general information on Head Start enrollment history:
Early Learning Initiative Awards
Preschool Development and Expansion Grants and
Race to the Top–Early Learning Challenge (RTT-ELC) (since 2011) funding here:
CCD is an annual collection of fiscal and non-fiscal data about all public elementary and secondary schools, public school districts, and state education agencies throughout the United States.
CCD home, more data
DOE's budget has a table comparing discretionary funding by state
not what you asked for
this resource library has data, essentially comparing each state's performance (or lack thereof), as well as local government activities/spending and comparisons. Its actually really high quality data.
Preschool Funding Trends by State Report:
NIER publishes a Preschool Yearbook with state data comparisons: