For these reasons, a well done but economical overview piece for your company is essential. It can be used for either pre- or post-show mailings, as well as for a simple informational piece for your "general" response packages and other mass mailings.
There should be some variation in the contents of your fulfillment packages. If you did a pre-show mailing, you should first take that mailing list and pull out the names of those who actually came to the booth (excluding the fish bowl people). To the remainder of that list, send a very basic package outlining your company's product or service line. Speak specifically about the success of the show and make sure you include an offer in the letter to encourage the reader to act.
To the contacts you made at the booth, send letters and contents specifically addressing their requests. These packages need to be personalized and should also include a specific offer that will encourage the contact to take action. Also, remember to state that a representative will be contacting the person by phone, and provide a range of dates for the contact time.