I spend a lot of time lighting my own product shots, or setting up visual environments, So I typically go out and capture HDRI's myself. Below are some quick samples that I use and will be making available for free download. In addition, I will be linking you tube video tutorials of how to capture your own, as well as what all uses you can derive from them. Stay tuned!
Technical information: All panos are shot from a Theta or Spherical lensed Cannon. Full res from the cannon is 10k and Theta is 5k. Each Pano is shot at 7 stops with a 3 stop spread. The Theta comes with a self stitching software package built in, but the cannons are stitched together using PTgui. Previews shown below have been crushed and optimized for web viewing.