you can just select analogLib vsource, in the Properties form (select the source in the schematic view and type "q") you will see a CDF parameter called "Noise file name" and the next one is "Number of noise/freq pairs". If you type "2" into this latter field, other fields will appear : Freq1, Noise1, Freq2, Noise2.
If you are exploring possibilities, you can just type there as many points as you like and see your circuits' reaction to that.
Otherwise, you can point the source to a Noise file. This is just a txt file with pairs freq/noise. You can run an AC simulation on another circuit and save the output to a file (as in saving a waveform to a table) and then use this output in other circuits, just by linking it through a vsource. Or through an isource, if the output of your previous simulation was an inoise :)
Hope this helps,