Chesapeake Energy Corp,the Oklahoma-based firm is the No. 1 driller in Ohio.
Rig Count Interactive Map by Baker Hughes, an energy services company.
Shale Sheet Fracking, a Youngstown Vindicator blog.
The Ohio Environmental Council, a statewide eco-group based in Columbus.
Earthjustice, a national eco-group.
People's Oil and Gas Collaborative-Ohio, a grass-roots group in Northeast Ohio.
Concerned Citizens of Medina County, a grass-roots group.
No Frack Ohio, a Columbus-based grass-roots group.
Fracking: Gas Drilling's Environmental Threat by ProPublica, an online journalism site.
Pipeline, blog from Pittsburgh Post-Gazette on Marcellus shale drilling.
Allegheny Front, environmental public radio for Western Pennsylvania.
Dozens of grass-roots environmental groups across New York have banded together to fight a plan to allow drilling for natural gas in the Marcellus shale in New York state.
They are opposed to horizontal drilling and hydraulic fracturing or fracking and want New York to ban it.
They intend to push their view in advertisements across the state.
The new coalition, New Yorkers Against Fracking, got a financial boost from activist-speaker-college professor Sandra Steingraber, who has donated much of her $100,000 prize money from the Heinz Award to fund the new initiative.
Other groups involved are Food and Water Watch, Frack Action, Water Defense, Catskill Mountainkeeper and United for Action.
Major national environmental groups such as the Sierra Club and the Natural Resources Defense Council support regulations on fracking but do not support a ban,
New York has been under a four-year drilling moratorium. State officials are looking at lifting than ban, perhaps later this year.