Add Cocoa Butter to Chocolate Chips to Temper?
Keep in mind that if you mess up tempering of 'fine chocolate', you can always heat it back up and do it again.  

All you are doing is trying to make one of the three types of chocolate crystals the dominant one, and form the crystal lattice.

This article chocolate alchemy describes it.  In practice, having a fast digital hand thermometer is really helpful since you can actually see the changes at the critical temperatures.

As far as the Nestle stuff goes, try practicing with them as they are.  I'm afraid I can't advise to throw good cocoa butter into it.  You may be able to get chocolate ice cream mileage from your 8lbs. Otherwise, just go ahead temper your favourite chocolate.  Worst case, a badly tempered good chocolate still tastes great.