When you think of oil, you may not immediately think of North Dakota, but the state is approaching record activity levels set in 1981. Driving this drilling boom is the Bakken/Three Forks play, which is proving to be one of the largest oil accumulations ever discovered in North America.

Given the strong drilling economics for onshore oil plays today, operators are throwing a tremendous amount of development capital at the Bakken. Continental Resources (NYSE: CLR) has 18 rigs in the play, which stretches across North Dakota and into Montana. The firm recently hiked its overall capital budget from $850 million to $1.3 billion in order to accelerate drilling in this and other "strategic" shale plays. Strategic, in this instance, can be interpreted as "not natural gas."

Another big player in the Bakken is Hess (NYSE: HES). The firm has eight rigs running in the play, which is a level of activity that Brigham Exploration (Nasdaq: BEXP) plans to match by next spring. Net production runs more than 16,000 barrels per day, with guidance pointing to a 20,000 barrel per day exit rate for year-end 2010.

This week, Hess filled out its considerable Bakken acreage with the acquisition of American Oil & Gas (AMEX: AEZ) in an all-stock deal. The transaction will add around 85,000 net acres to Hess' land position, which weighs in at more than half a million acres. Prior to this acquisition, Hess had set a production target of 80,000 barrels per day by 2015. It's possible we could now see that target hit a bit sooner.

If you picked up shares of American Oil & Gas at any point last year, congratulations. You've netted yourself a handsome gain. If you've still got the Bakken bug and find yourself looking to redeploy your investment into a player with a tighter focus than the internationally diversified Hess, there are several options.

One of my longtime favorites is Northern Oil & Gas (AMEX: NOG), a company whose strengths lie in land acquisition rather than drilling. Another company I'm much less familiar with is Oasis Petroleum (NYSE: OAS), which just came public last month. I'll offer a review of this company in the weeks ahead to see if it's worth your Bakken dollars.