A bundle of useful info from this – The Pocket Guide to Transportation – from the U.S. Department of Transportation.

Like what governments spend on highways and transit:

Transport Expend


And what revenues they get from highways and transit:

Transport Revenues


Let the interpretations begin.  (Like expenditures going up for highways, revenues going down.  For transit, both going up.)  And look at how the feds cut transit expenditures in 2007.

UPDATE: Eric Doherty provides a comparative link for Canadian spending on transit –