Yep... need to be rooted for free wireless tether (hotspots). Once you are you have apps like Wireless Tether for root users, Open Garden Wifi Tether, Barnacle Wifi Tether, etc...
I just had to explore this option recently as our home DSL service has been down since last Friday (due to an area network issue they're still working to fix).
Since I'm not rooted and have no interest in doing so, I just added the "4G Smartphone Hotspot" feature to my account (It's listed at the bottom of the "Change Features" area under Internet Access). It's an additional $30 a month on top of your data plan. I can confirm that adding this does NOT affect your existing data plan, so no worries about losing grandfathered unlimited data. Also, you can drop it at any time and it'll be pro-rated for only the time you used it. I was able to use the My Verizon app to add the feature, then just turn on the native Mobile Hotspot function of the phone, configure it along with the PC and I've been back online since. No worries about trying to root or get caught using unauthorized tethering.
This option really makes me appreciate my Thunderbolt even more. And the fact I can still make voice calls while using the hotspot (simultaneous voice/data): priceless. This phone rocks!