My project integrates PHP, MySql and XML data sources. It is a niche search engine which runs queries on affiliate sites and then parses and crawls the data direct or via XML and API access serving the content to the users. A similar site is [url removed, login to view]
No graphics and design are needed just the script.
For more questions feel free to let me know.
A working demo can be seen here http://www.carrentals.co.uk/
I am trying to achive the same functionality or similar (the design is not included, i have it already)