Face it, we live in a very busy world! The editor who is not calling you back is possibly interested in your story for your product, but just hasn't gotten to you yet. What do you do? Pick up the phone and call him!
The same holds true with all the business cards you received during the last trade show. Don't wait for them to call you, follow up with them. Ask if there are any questions you can answer, or any additional information you can supply.
One of the best things you can do is keep notes in your day timer as to who to follow up with, and when. Don't trust something as important as follow up to your memory, it doesn't work.
Carve out blocks of time each day for follow up, and call those customers who are hanging on the edge of purchasing your product. Make sure you know what their objections are, and work to remove them.
If you have someone who has committed to have a project done for you in a few days, call and follow up the day before it is due to make sure it is on track.