The industry has several trade associations that are excellent sources of information with an industry slant.  There are innumerable resources to gather information about the specific companies.

Universities such as Penn State and Cornell are providing a wide array of Marcellus related information with a neutral voice.  Other community organizations like the League of Women Voters are doing similar work.

From in depth research pieces to graphics to videos, there is plenty of good information to educate yourself on gas drilling, fracking and beyond.

These research papers work to measure the potential postive economic ripple effects from Marcellus drilling and investment: local business activity, employment, reinvestment of lease payments, etc.  Some weighing of the rewards with the risks.

Many organizations from the industry to environmentalists to blogs will push information to your email address when you sign up.  Most are informative.  Some do more filtering of the flood of information than others.  Here is a sampling.

These tend to be not so well organized but do provide interesting forums for discussion

There are more than 100 companies just drilling in the Pennsylvania Marcellus Shale.  Plus 100s of others providing support services from water trucks to fracking chemicals.  Most web sites have investor relations pages where you can find Securities & Exchange Commission (SEC) documents, presentations made at industry conferences and conference call transcripts.  All of these are excellent sources of detailed information about public companies.