Earlier this week, Revolution Analytics' Joe Rickert gave a webinar Introduction to R for Data Mining. You can watch the replay below:
If you're already familiar with R and the basics of data mining, you might want to skip ahead to the 13-minute mark where Joe's live demo begins. There you'll see practical examples of using R for decision trees, random forests (with fast parallel processing), support vector machines and (with the big-data capabilities of Revolution R Enterprise) K-means clustering on millions of rows of data.
Joe also provides some handy links to data mining resources near the end (at 50:00). You can find the links to those resources in the Joes slides, and also the annotated R scripts used in the demos, all downloadable at the link below.
Revolution Analytics webinars: Introduction to R for Data Mining