Sir/Madam,
On behalf of __________ (organization name), I would like to inform you that our organization has planned an event on date __/__/_____ (date). So, I request you to book a venue for approximately ______ (number of people). We have heard a lot about your _____ (catering/any other) services, and we would love to organize our event at your venue.
Therefore, I request you to kindly confirm the availability and if possible reserve the required venue and confirm the same on __________ (mention email ID). If you have any query, please feel free to contact Mr./Ms. __________ (name) at ___________ (contact number).
Yours Truly,
_____________ (Name)
_____________ (Contact details)