Go to [spam] once all the categories come up find *health and fitness*, on the next category list find *fitness and wellness*, then find *sexuality*, then *how to have better sex*. Once that is up go to the very bottom of the page under the thick red line and click on previously asked questions, go to page 2 of that and find the question 'lasting longer' it will be answered by fox saheli.
Apparently this guy formally studied human sexuality. He's a pro. If you're curious about anything else find any other question on that site that he answered. By the way, this is free. It's just a question and answer site.
Unlike [spam] who wants fifty bucks for 3 books about this.