You can have the Arduino count the wheel rotations and calculate the speed at regular intervals e.g. 100ms and print it out over the serial port. The Arduino application software includes a USB driver which presents the Arduino's serial port as a virtual COM port that can be read by any application. For prototyping purposes you could just use the serial port monitor provided by the IDE, or anything else you can find that can read a COM port (older version of WIndows used to include a terminal application that could do it). Which one is best for you really depends what you want to do with the data. If you only want to load it into a spreadsheet and do your acceleration and torque calcs, using Gobetwino to log to a CSV format file would do that easily enough.