ok first off.. arent the motor and engine the same thing?
if you want a conversion a jdm type R motor runs you around 5000-5500. sometimes you can find a whole clip with jdm front and rhd for around 6k, found someone in orlando.. was a hell of a deal.. normally when you get a full swap you get everything, motor,tranny,ecu,axles and shift linkage..

otherwise you can normally pick up a gsr for fairly cheap. and that would be a good bit faster then the LS.. otherwise just turbo the ls for some decent power..

as for wheels depends on the color of your car.. however 16's are normally the best size if you want to be performance oriented

and for the exterior either a jdm front end conversion or a nice type R lip, and the honda optional side skirts look great

if you need any info just holla