Okay, these are the tour dates Coheed and Cambria has posted this September. As this description shows, the 9/29/12 date in Atlantic City will have all of them on the bill. I also noticed my friend Neesh on facebook mention the Rochester, NY Coheed show on 9/21/12 will include 3 as well (but not necessarily The Dear Hunter).
I imagine this short Northeast tour could include them all. Not that it is so relevant to myself living in Minnesota, but it is a pretty cool 3-band bill, that I'm sure some folks will want to check out, if they are a fan of all of them, or 1 or 2, or just progressive rock in general.
edit: this link shows the modified Tour Schedule below shows
The Dear Hunter: only for 9/28 and 9/29 dates
Three: 9/13, 9/19, 9/20, 9/21, 9/22, 9/24, 9/25, 9/26, 9/28 and 9/29.
13 Kingston, NY - Ulster Performing Arts Center*
15 Chicago, IL - Riot Fest Chicago
16 Charlotte, NC - WEND Wienie Roast
19 Buffalo, NY - Town Hall*
20 Toronto, ON – Mod Club*
21 Rochester, NY - Water Street*
22 Albany, NY - Hart Theater at The Egg*
24 Syracuse, NY - Wescott Theater*
25 Burlington, VT - Higher Ground*
26 Hartford, CT Webster Theater*
28 Worcester, MA - Palladium**
29 Atlantic City, NJ - House of Blues**
* w/ 3
** w/ 3 and The Dear Hunter
tickets are available here