I have used, successfully, this fax number directory list. It obviously doesn't list EVERY fax number in a particular city, but it can give you some good ideas. We had a local tax preparation business give us a cash donation. So, you never know?? Here's the link....
fax.addresses.com/fax_directory.php
Also, remember to try states and cities near you. We get a good response from maid services and family oriented places of interested from other states. For example, we're in Henderson, Nevada (suburb of Las Vegas) and we get stuff from Montana, Colorado, Wyoming, etc. It's nice for our parents to bid and win a gift certificate, etc. for a new fun family vacation spot to try.
We also have classroom baskets. That where I post a list of theme baskets in the teacher's lounge. If a teacher wants to participate, they choose a theme and solicit donations from their parents and businesses. These are in their own section in our silent auction area. All of the money raised by that classroom's basket goes back to that classroom. So, for example, we have a 1st grade teacher that always does the "Warm up with a good book" theme basket. She collects children's and adults books throughout the year and has parents donate new books. She also has her mother-in-law sew a quilt with each square that is either each students' hand print or something like that with that student's name embroidered on their square. Last year it was won with a bid of $165. That's super for our parents. She's doing something similar this year. We (the PTA) deposit the funds that particular classroom basket earned into the teacher's school account with the office manager.
Good luck to all of you,
Holly