Here are links to some of the resources I use
Out There Learning with Julian Thomson - great resource for NZ geology videos
https://www.youtube.com/outtherelearning
GNS National Paleontological Collection (index of New Zealand fossils with photos)
www.gns.cri.nz/data-and-resources/national-paleontological-collection/
New Zealand Molluscs (including shells)
www.gns.cri.nz/static/Mollusca/index.html
PDF copy of Beu & Maxwell 1990 [86mb] - 500 pages of fossil shells
www.gns.cri.nz/static/Mollusca/p_bull_58.pdf