How to get old Spotlight Search View back for Yosemite?
As of today there is no way to move/resize the spotlight window or to rollback to the previous spotlight (as seen on older OSXs)
I would suggest giving a feedback to Apple about this.
Here my second bug report to Apple
I was also annoyed by the obtrusive, centrally-located spotlight window. My only solution was to move the window into the upper-right hand corner. OSX remembers the window position so it always reopens in the upper-right hand corner for me now. Slightly more palatable then the original position. Hope this helps!