Here is an online copy of the presentation I gave today at WordCamp NYC:
I also have some supplemental links here for you to further explore listings and vendors of premium plugins:
Directories and Dashboard Addons
Commercial Plugins | WordPress Honors (somewhat out-of-date)
Plugin Collections (including commercial services)
Individual Premium or Pro Plugins (note: these are not recommendations; just a list of found plugins)
Wufoo · Online Form Builder and Wufoo Shortcode Plugin