The name pretty much says it all. We (my band an I) have no problem getting shows with other locals or even other cities, but we want to learn how to books shows with national acts. Most of our band friends are more or less in the underground scene here, so seeing them with a national act is pretty rare. We however, don't want to stay underground, we want to spread ourselves to as wide an audience as possible. I understand that many national bands having booking agents that handle these things. Do we try to contact them or the venue itself?
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I think it kind of depends because this summer my band opened up for the Carnival of Madness tour in Milwaukee by just emailing the Rave/Eagles Ballroom. We had to pay $500 but we got $1000 worth of tickets to sell.

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Still comes down to networking.

I'm sure there's some national act around your area in the same genre that you're playing. If you truly are drawing a decent size crowd, mention it to the band and go out to one of their shows and talk to them afterwards. Just mention and then follow up later that you would love to open for them the next time they play at *insert venue here*. (mention, were from the same town, grew up here, love the music, etc.) Sell yourselves.

It always comes down to meeting people and making friends with people in other bands. If you get in with someone they might take you out on tour with them or at least start asking you to play with them frequently if they like you.

As far as booking agents go, you can shoot them emails with press kits. Some local festivals are easy enough to get on even out of state if you get in touch with them early enough. Just do some research into it.
Well you are most likely not going to be getting on the bill with really big bands at this point. But bands who maybe are past their hayday, or bands who are on a national label but still not big enough to fill a big venue are possible to get. In those cases I think it is more booking through the venue than through the band. It's all about numbers, they don't want to book you if they don't think you can bring in people and make them money. Show them your numbers, facebook fans, song downloads, other venues you have played, if you can consistently get a certain number of people. Believe it or not the people who book these shows know what is going on in the local scene. If you are big enough, they'll know who you are. This also goes with making contacts. It's much easier to book a show if you know someone, either in another band, or someone high up at the venue. You'd be surprised who knows who. One band I was in was able to book us a show opening for Adema at the Whiskey a Go Go. Not a huge show, but a fairly big venue, and opening for a platinum selling band was very cool. What's better is that because the show wasn't huge we were able to hang out with them after. We talked to them, their agent, and made some very good contacts.
Play a lot of gigs. Play as often as possible. And always chat up with owner/manager of the venue, who often doubles as the booker.
You're not going to open for U2 - a huge tour like that has an opener that tours with them, is usually picked by the headliner, and that's if there's a support slot at all. You need to be looking for mid-level bands, who might be touring with a few support groups, but whose shows will usually have a local band as the first one on, in order to generate a bit more drawing power.
I once opened for the Canadian pop-punk band Gob - it was a few years past their heyday, but they were still fairly popular. We got the gig because the venue owner knew our band, knew we had a good sound for the show, and knew we would draw an extra 40 people, even if we were playing 3 hours before Gob hit the stage.
So, as with all things in life, it's not about what you know, but who you know. Be the band that the venues like, and you'll be set.
The key is to network as much as possible with bookers, bar owners, and other bands. My band has opened for nearly a dozen or so national acts in the past year or so and that's mainly because we knew the people booking the shows or the owners of the venues.

Normally, the local bands booked to open for national acts are the bands who are pretty well known in their region, put on a good quality live performance, and maybe most importantly are bands that generally draw and hold fairly good crowds.
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