Northeast of Queenstown and Wanaka, The Plantation (aka Sticky Forest) is a popular MTB trail network. These trails connect with the with Hikuwai Reserve trail system.
This is pretty much it for singletrack riding in the Wanaka area.
To reach the mountain biking trailhead from the center of Wanaka, head north on Lakeside Road. Veer right heading north on Beacon Point Road. Turn right heading east on Aubrey Road. Turn left heading north on Rata Road. Turn right heading east on Forest Heights. Turn right on Platinum Ridge into MTB parking area.
Alternately, you can mountain bike ride from town on the Lakeside Track on the shores of Lake Wanaka.
Overall, The Plantation is the 23rd most popular mountain bike trail of all 41 mountain biking rides in New Zealand.