you are looking for screenwriting seminars, most are annual
events. So if you missed the seminar the previous year, there's a good
chance there will be another one in future years.
Borowski lecture on screenwriting:
for the Borowsky Lecture are $5 for the general public and $3 for
students with valid identification."
indiewire.com and Script Magazine websites both promoting Linda
Cowgill seminars--"For more information, go to www.Plotsinc.com or call (310) 383-6322."