You can check out our recommended cameras here: http://vsee.com/blog/best-webcams-video-calling-review/
Other similar web cameras are also fine - please look for "HD 720P" and "auto focus".
Please note for a conference room set-up, in general, it is difficult for a single camera to cover an entire room - you could get a Minrray PTZ Camera which VSee sells (Contact firstname.lastname@example.org for a quote). Other good cameras that work well with VSee are the Logitech cc3000e, PTZ Pro and PTZ Pro 2.
Alternatively, you can use multiple webcams for more coverage. See for more info: http://vsee.com/blog/conference-room-setups-1/
The older Sony Evi and the Logitech Orbit AF and BCC950 used to work with VSee, when connected through a specific video adapter. However, their configuration is much more prone to errors and they are harder to set up due to the amount of cables required. We do not recommend these cameras any longer.
If you have any specific camera related questions, please don't hesitate to contact email@example.com