Where in the world????

For the past several weeks,I have been unable to "find" Without a Trace on my local broadcasts. If it's not been pre-empted, I don't know when it's showing anymore, and I missed the finale, even though all online links said it would be shown May 18th! It was not, and the finale of CSI was broadcast. How did this wonderful show take a hit like this?? Are re-runs scheduled? Where could I watch the video? I'm a first time 'fan' here and have not looked around the site that much yet. Thank you. SaltRiver