An amazing collection of papers from CHI(Computer Human Interface) 2003 - Best Practices and Future Visions for Search UIs: A Workshop.
A few of ones that quickly caught my eye (I'll be reading them all, and recommend that you do the same):
* Nichola J. Belkin, Rutgers, "Interface Techniques for Making Searching for Information More Effective":http://home.earthlink.net/~searchworkshop/docs/belkin-final.pdf
* Joel Angiolillo, Verizon Wireless, "Search Log Analysis as a Usability Engineering Tool":http://home.earthlink.net/~searchworkshop/docs/chi-search-angiolillo3.doc
* James Kalbach, Razorfish, "I'm Feeling Lucky: the Role of Emotions in Seeking Information on the Web":http://home.earthlink.net/~searchworkshop/docs/JKalbach_Emotions-InformationSeeking-Web_short21.pdf