Best places for placement of advertising flyers depends on what environment or neighborhood you live.
Think of yourself where would be the best in your area.
For example:
1.urban transport
2.supermarket
3.cafes, pubs
4.a university bulletin board
5.in the post
6.at sport events
7.concerts, cinema, theater
and similar.
Most important is to post at any place where a large movement of people every day.