I think Sarge has seen this before, but I figure it wouldn't hurt to post:
I have been sending out packets almost since day one. I can tell you that they have gotten me a LOT of business- on two levels.
Since I do bar/restaurant venues as well as private events, it's my first intro, mailed to the owner, followed by a visit, then a call- repeat. Again, this is for bar work
For venues such as banquet halls, I visit first, and get all of the contact names that I can- THEN send packets ( These people also get holiday cards and the like). Not just the G.M. or Event Coordinators, but banquet captains as well. Also, when working, I make a point of being very friendly toward waiters and bartenders during set up and breakdown.. Thus, when the time comes up, I am remembered and referred. One local banquet hall has been directly responsible for referring what came to 17 events just this year.
I send out three different types: Bar or Banquet/Event Venue to businesses, and a third type to the potential client.
One HUGE suggestion in regard to packet content- and I can't stress this enough:
MAKE IT MEMORABLE! Yes, I'm sure you think of professional graphics and beautiful fonts, but if they look like everyone else's beautifully done corporate stuff, they will end up in the can.
Mine happen to be some of the most non-professional looking, printed on chartreuse paper, with an eye-catching font. Ugly as hell- But the venue mgr. will have it on the desk even 6 months later... Instead of 2 or 3%, I average a 7- 10% response on my mailings.
Oh yeah, lose the graphic or pic of you with one hand holding the headphone to your ear, head slightly tilted, the other hand fondling your mixer. That's probably ASKING them to throw it out. ( no offense if that happens to be your avatar

- it's just overdone) If you are going to use a picture of yourself, use one with a SMILE, not the "cool" face. Same with the softly lit romantic picture of the B&G, both hands clasped to gether and looking into each others' eyes. It's everywhere. This last paragraph is more than just my opinion, it's feedback from those I contacted. Also, when I started, I used those types of graphics, and got a WHOLE lot less response.