My federal taxes were not withheld, because I was receiving stipends. Therefore I owe almost $2000. What are my solutions?

First are you sure you owe 2000,

But you file and work out a payment plan for the taxes

That's what it appeared in according to calculations done in Cintax. I haven't had any federal taxes withheld for 2010 and for 2009 I had almost $2300 withheld, but during that year I was not receiving any stipends. In 2010, I received stipends only from August till December.