Thanks for all the different sources of US data some of you have posted, from looking at it it would take a long time to get basic data for the entire US, and of course there is no guarantee that the plotted positions would be right if I rush through as many as possible.
What is probably most practical is if you want traffic data for your area, suggest the best source that you would feel confident in trusting. I don't know america and am reluctant to spend 3 days creating code to import the data if to later find out the data is no good to anyone!
In addition to this, if the source does not offer lat/lon positions then the best alternative is to do the same as veetid and map these locations out on MapPoint with names that match the locations given out on the web site as pushpins. I can export these pushpins as lat/lon and add them as references in the database.
The web site format needs to be machine-interpretable to some degree, at best this would be TSV/CSV/XML format with lat/lon, at worst a text page set into tables with common descriptions of locations; i.e. the page would have been machine-generated. Flash/graphic based pages are more complicated, but if that is the only data source for your area there is a possibilty that the data is pulled from a text-based source behind the scenes (i.e. Trafficmaster in the UK) so if there is no other option I will give it a go.
If you're better at me at coding (which doesn't take a lot) you might want to write you own app to download, parse and upload the data. If so let me know. I have no problems in releasing the source to anything I write to do with this or the specifications such as db table structures.