Getting Latitude and Longitude from a Street Address

The Simple Statement
A method is described for determining a latitude and longitude when given a US street address. The technique uses the Census Bureau data files. Not all addresses can be successfully geocoded, but the results are promising.

An abbreviated view

Determine proper county based on zip or city name to county mapping (this becomes unnecesary if all data is in one table).
Locate possible street match candidates. Record Type (RT) 1 includes zip codes as a crutch.
Walk the list of candidaets. Verify suffix (dr/blvd/ave). Validate zip code on that record. (The issue is that we have street segments. We need to assemble a full line for a street (maybe not...see next steps).
Extract address ranges
Determine odd/even for side of street
Select proper street record based on address ranges
Extroplate lat/long based on start/end of street segment, and the % of the way that this house number is between the start/stop.
example: assume start/end range is 200-295 (house numbers). Then '250' is halfway between the start and end lat/long. We will be off by a maximum of 1 block (but 'block' might be a long ways!).
Consider using more shape records (RT 6?) for more precision.

10/17/2000-an attempt to automate a geo coding application 10:45pm Start work
12:08am A rudimentary app exists. It does find the correct block, often, but does not try to extroplate the lat/long based on %'s of address within the range, and it is not very smart or user friendly. It also doesn't yet use zip codes-which will help.

Thoughts for Enhancements

I don't need non-road features in my data! This is a thought for dealing with a truly massive amount of data (as I try to move to have full coverage).
Linking to my map would be cool...but what scale? What features? This brings up the key question: how do you automate what is, at heart, an aesthetic and artistic choice?

Tentacles of despair.
file created 10/17/2000 original as: //icarus/geo/geocoding.html