Bespoke programme required for existing website

I am looking for the most effective solution in getting client's stock information from their website onto my web platform (this includes stock description and images). Potentially this could involve 50-100 different client's who hold their stock information on different formats.
Previous discussions have involved web scraping, robots and spyders.
The solution must be fully automated to enable stock details to update daily.
Previous direct experience of something similar is essential (no sub contracting).
This will be an ongoing project into 2011.