There's an outdoor track in Mission, indoor arenacross in Chilliwack a few weekends in the winter, an MX track on the island in Victoria. Probably more, but I'm a woods rider, so I don't know for sure. Check out www.pnwma.ca or Holeshot Racing for additional info.
There are motocross tracks in Nanaimo, Mission, Kamloops, Kelowna and outside of Castlegar. I'm sure there's more that I haven't heard of. I race harescrambles and cross-country all over BC and have a pretty good knowledge of riding areas. If you have any questions, reply to this thread or email me.