I'm not based in the USA, but I've only heard good things about the TIGER geocoder, and it seems to be the best complement with PostGIS. To quote that link:
The goal of this project is to build a fully functional geocoder that can process an arbitrary United States address string and using normalized TIGER census data, produce a point geometry and rating reflecting the location of the given address and likeliness of the location. The higher the rating number the worse the result.
The reverse_geocode function, introduced in PostGIS 2.0.0 is useful for deriving the street address and cross streets of a GPS location.
The geocoder should be simple for anyone familiar with PostGIS to install and use, and should be easily installable and usable on all platforms supported by PostGIS.
It should be robust enough to function properly despite formatting and spelling errors.
It should be extensible enough to be used with future data updates, or alternate data sources with a minimum of coding changes.