Question : Custom GIS Application - how to use map data

Hi,
I want to develop a program that will take a lat / long co-ordinate reverse geocode it to an address and then give the posted speed limit on that road.

The data I need comes in the following formats
  - ESRI Shapefile (.SHP), or
  - MapInfo Tables (.TAB) or

Once I have the data, can I put it in a database and write a .net applicaion to do what I need?
Or do I need a special GIS application to read the data?

Please point me in the right direction.

Regards
sm17ch

Answer : Custom GIS Application - how to use map data

Oh, I see now.

One question, are You sure You will get speed information from this files ?
As I can see in description of this file types this is not in default format.

The most complicated in geocoding is to find out to which road is the point (lat/lon) is close.
Probably, if You will convert data from SHP-TAB files to SQL database, You will be able to use SQL possibilities to find out it easier and faster.