Most search engines include user interfaces and query languages which are tailored for use with specific file types. Thus, a user interface for searching one type file can be quite different than an interface for searching another file type. Disparate user interfaces are troublesome since users must continually reorient themselves as they switch from interface to interface to initiate searches for different file types. Additionally, many of these user interfaces use different query languages and structures, which are not generally adaptive to new file types and query language features. Accordingly, the present inventors developed an adaptively configurable user interface to facilitate a common user experience across two or more databases and an extensible common query structure to allow expansion of a query language to meet the demands of new file types. An exemplary embodiment includes a discovery mechanism for determining query properties of search providers, thereby facilitating adaptive configuring of a user interface to expose the determined query properties. An exemplary embodiment of the user interface includes a portion which remains relatively constant across two or more search providers to reduce user disorientation.