On CreativeLive, there will be a 3 day FREE class on using PlugIns in Photoshop and Lightroom.
I watched one of the earlier shows on Lightroom and it was what really sold me on getting Lightroom. For me, it has been the most intuitive software so far. (Thank you Esther for your periodic recommendations on these classes.) Of course if you miss part of one or want to watch it at your own leisure there is the option to buy these classes too.