what kind of rims ,are your stock rims?
you probably don't need anything .i bought some kenda k rads 2.3 ,and they run like a charm .they are not slicks but super fast and also give good tracktion on wet roads ,which slicks don't .they also have k rads in 1.9 on nashbar.com . i run them on 80 psi .
the best thing about these tires is that they are also super cheap.i would buy those if you want to keep some benfits of the mtb but need to go fast .