If you want the lockets:

You find them on the ebay site of your country (that's where I got mine) just search "h2o just add water" on ebay.

Fansite for h2o and mako mermaids:

www.makoislandresort.com

Official h2o shop:

link

You can find there mermaid tail,jewelry,dvd's,books and other stuff (mako mermaids stuff 2)

I hope that this helps :)