where do i find the collection of new wavetables in kontakt 7?

That is a strange answer.

Normal users can easily use wavetables in Kontakt. No need to know anything about instrument building (KSP scripting, custom GUI design, etc).

The wavetables and single cycle waves are in "C:\Program Files\Common Files\Native Instruments\Kontakt 7\groups\Wavetables\Samples" folder on Windows, probably something similar on Mac. For easy access, you can add and lock that folder to the Quick-jump entries in Kontakt's Files View menu in the Side Pane.

There are two new subfolders: "Single Cycles" and "Wavesets". And some of the new wavetables have been added to the existing "Additive", "Digital" and "Formant" subfolders.

And when using wavetables in Kontakt, it becomes a very capable synthesizer, not just a sampler.

Using wavetables in Kontakt is not much different compared to using other wavetable synths, like Massive. Actually, many of the included wavetables in Kontakt have been taken from Massive.

Using a synthesizer, creating synth presets, is traditionally not considered "instrument building".