Where can a small business advertise for free?

Update again: I was at Border's book store the other day and I was looking to see if they had a bulletin board for advertising or not. I found it, it was by the restrooms with a sign that said "advertise your non-profit event here". I was saddened at first, but right away I spotted a multi layer stand for business advertising. There were a lot of postcards in the slots from local businesses. So I left my cards there, and I was very thankful to Border's for supporting the small business. So I am changing the title to this post to "Where can a small business advertise", because I am now on a quest to find all the bulletin boards in my neighborhood. So, keep watching this post.

Update: I wrote to Panera, and they responded as follows:

"Thank you for contacting Panera Bread. Our bulletin boards are to be
used for non-profit organizations only, not to promote advertising of a
business. We apologize for any inconvenience that this may have caused

So today, I asked the same question from Starbuck Coffee house and received the same response :"They are not allowed to advertise other business". Well, needless to say I am very saddened about their policy. I changed the title of this article to say "Did you Know, Coffee Shop Bulletin Boards are not for business advertising?".

It is no secret that I am a struggling artist with a very small
business. That means my advertising budget is almost non-existence.
So, I had to get very creative to come up with free to very cheap
advertising. One of the ways I advertise is by printing promotional
flyers and post cards and posting them on community bulletin boards
around the town and everywhere I visit. I am always in search of
community bulletin boards and have found them in a few coffee shops and
Panera Bread Restaurants. Yesterday, as usual I went into a Panera
Bread Restaurant to place my Ad on their community bulletin board and I
noticed a sign saying the board was for non-profit ads only and to see a
manager. So, I found the manager and showed him my Ads, he said "we
cannot promote other businesses". So, saddened I left the restaurant,
thinking I will never come back. It is their restaurant and they can do
what they please; however, I wonder why they cannot support the local
small business owners, why they cannot support the handmade movement.
After all it is a community board and I am part of the community. I
sell handmade jewelry; one quick look at my ad was obvious that in no
way or shape I was taking business from them, I was no threat to their
business. So why turn down a small business in your community?