Wow! Such great pics. The in camera HDR is terrible! I must get one of the HDR plugins. Suggestions please
I think the two most popular ones are Photomatix and Nik Software's HDR Efex Pro. Photomatix is cheaper (now that all Nik plugins are bundled together), probably more powerful and with a steeper learning curve. HDR Efex Pro costs more because all the Nik plugins are bundled together since Google bought Nik, and I think it's a little easier to learn but doesn't give you the level of control that Photomatix does. If others disagree, please correct me; it's been awhile since I used Photomatix.
The upside of buying the Nik bundle is that you get five other plugins, too; Silver Efex Pro, Viveza and Color Efex Pro were all particularly useful additions for me.
Really, though, I don't think you can go wrong with either option for HDR processing.