Hello vsats,
I do not have all the exact dates handy but I can give you a rough estimate on how long it took for my N400 application to be processed. I submitted my application to the Nebraska service center on april 22, 2003 and got the leeter for my fingerprints in may, my fingerprints were taken on June 7th, 2003. After that I received my notice for the interview in mid july the citizenship interview was on August 27, 2003 at the Denver INS office. Furtunately I passed everything and was given my oath ceremony date at that time, the oath will be on October 10, 2003 in the Denver INS office.
Hope this help