As referenced in many articles, being good at selling is a work-in-progress. It is a journey, not a destination.
Case in point: There are long time sales veterans who admit to learning new things every day. This is what keeps us going - the ability to be open to things we have not tried before, or we have not focused on for some time.
So where do you learn? AllBusiness has articles on selling. There are audio products like Sales Rep Radio as well as Selling Power Live. I enjoy reading the other bloggers on AllBusiness for different viewpoints, as well as others who post on the Web.
Do searches on the Web by phrase or name. Find a mentor - someone who excels at sales in the type of selling you admire. Ask them if you can meet with them periodically.
When I wanted to become a charity auctioneer, I saw an amazing auctioneer in action and followed up with her after the event. Eventually I went to auctioneer school in the Midwestern U.S. (yes, with cowboys and everything)and have been auctioneering ever since. Just last week, my mentor, veteran auctioneer April Brown did an event with me. So I've come full circle. I have tons to learn when it comes to auctioneering - by the way, I think it is the ULTIMATE in selling.... but being on stage with my mentor was a big milestone for me.
Take a risk - learn something you don't know. See how it helps you to sell better, and post your comments.