As far as I know (haven't verified every one) all the EVDO phones can all be tethered, either via Bluetooth or cable. You can't see the deatils until you bring up the page for the individual phone and view its Bluetooth (look for profile called Dial Up Networking) or a cable coonection (usually called High Speed Connection).
For a phone, you add the Broadband Handset Connection FEATURE, with the key word being "feature". There is no contract associated with a feature, so it can be turned on/off at will. The Feature costs $59.99/month but it is prorated, which works out to $2/day it is in effect. Note that you pay as long as the feature is in effect, whether it is actually used or not. You start or stop it with a call the Verizon Customer Service and it takes effect immediately. The Broadband Handset Feature has the same data capability as the Broadband contract - up to 5 GB/month and unlimited connect time.
Verizon does a good job of hiding this info and keeps leading you to Wireless Broadband contracts, which apply to data cards and not phones.
To find a phone, view All phones on the VZW site and then filter (using the search filtering on the left side of the page) for the Mobile Broadband capability. That will get you a long list of phones and data cards, but they all can do it. Problem is, Verizon doesn't always have the modem drivers for all these phones and that sometimes stops them from offering the Feature for it. You can get the drivers & cables elsewhere, but their system isn't geared to let the reps accept that without a struggle.
The PDA plans are cheaper but do not include tethering. You only get tethering via Broadband Handset Connect. Since a PDA already has a limited connect as part of its voice plan, they allow an upgrade to provide tethering and it brings the total cost to the same $59.99/month that you would pay for a non=PDA phone. No free lunch there.