This webinar by Soundforge actually focused on audio capture for streaming from a lecture setting rather than a controlled desktop recording. Some of the information could be useful for workshops or other big group activities.
Choose a mic for the setting and number of speakers - omnidirectional for wider range but more background noise, or unidirectional for a single speaker.
Mic the speaker when you can. Lavolier or lipstick mics, overhead or pressure zone (e.g. gooseneck) mics can work in the right range.
For large rooms parabolic mics work well IF they are precisely aimed. Gated mics that turn on when a person speaks can work but may have a slight delay before they are audible.
Automatic mixers can work - they provides gating and can stack people when several want to speak at once.
A DSP - digital signal processor, part of an automatic system can be very helpful if it automatically turns off the loudspeaker in the area when a mic is turned on. This increases the gain without increasing the feedback.
Notes from this webinar are in the VSDL Share folder in Webinars/audiocapture_091203