There is no real need to amplify the output of your c.t. The output is 1 V rms - depending on the shape of the current wave, this should represent a peak to peak voltage of a little less than 3 V, the standard Arduino input range is 5 V, so you are only losing 40 % of the range - less than 1 bit of input resolution.
You will be able to use emonLibCM with your Arduino, which will Continuously Monitor the inputs.