How can you calculate the energy required to propel a certain mass to near light speed velocity?

E=mc^2

edit: oh and I'm not trying to be funny, but isn't that the formula? m is mass c is the speed of light and you square that to get the energy?

Calculate the relativistic kinetic energy your mass, "Mo", would have at velocity "v". That will be the minimum energy required to get it moving that fast.
The formula for relativistic KE of rest mass "Mo" and velocity "v" is;
KE = Moc^2 - Moc^2/Sqrt[1 - v^2/c^2]  , where c=speed of light, 3x10^8 m/s  and Mo is any mass you want to use, in Kg.

EDIT_________________________ _____________________________ ___________________
Sorry, I wrote that eq. backwards. The relativistic KE is;
KE = {Moc^2/Sqrt[1-v^2/c^2] } - Moc^2

If the velocities are in m/s and the mass in Kg , the Energy will have units of Joules.
 Since 1J = 1Kg-m^2/s^2

You will notice that as "v" gets close to "c" the first term becomes so large that subtracting the second term (the so called rest energy) will hardly effect the answer and the KE is approximately equal to the first term alone. The first term is called the Total energy of a moving mass and is often just written as "Mc^2" where M=Mo/Sqrt(1-v^2/c^2) , which is referred to by the above answerer.