The venues that are commonly used for seminars tend to fall into two broad categories.
The first category of venues that are commonly used for seminars is that of those that are owned by educational institutions. These are typically used to host educational seminars, especially those that are associated with members of staff affiliated to the respective educational institutions.
The second category of venues that are commonly used for seminars is that of those that are owned by individuals, and run commercially. If you are keen on using these types of venues, you just get in touch with their owners, pay the requisite fees, and get the chance to use the venues as you wish. Of course, before all that can happen, you normally need to contact the people in charge of them, to enquire about their availability. But that can be something as easy as going to the Gmal.com sign in page, where you proceed to log in to Gmail and having done so, proceed to send an email to the people in question, asking them to consider availing the venues to you. Since these are commercial venues, chances are that you won’t have difficulties securing them, so long as you are ready to pay the required fees.