How to add managed property and configure advanced search in SharePoint

Here is very good detail information about how to add managed property from central admin site and how to use same managed property into advanced search page:

http://waelmohamed.wordpress.com/2011/05/31/add-custom-search-properties-in-your-advanced-search-sharepoint-2010/

How to add new managed property and customize advanced search page

We can customize search and advanced search page, by adding properties to it, generally all columns which we created into site comes in crawl properties when we do FULL CRAWL of the SSP. So then after we have to create new managed properties from going to SSP->Search Settings, we have to mapped crawl properties to manage properties and we can use those all managed properties into customization of advanced search page by adding “Properties”  into it.

You can find all these stuff from below links

http://jopx.blogspot.com/2006/08/add-document-properties-to-advanced.html

http://www.mosssearch.com/searchcolumn.html

http://www.codeproject.com/KB/sharepoint/MOSS_Advanced_Search.aspx

How to add property into advance result page