Not sure why I can't seem to turn my selected object (icosphere) to a halo when I try to make a new material. The options just aren't showing. Thanks]1
If you are in Cycles there is no halo material. You'd need to make one with a particle system:
Static particles would work best for this, so you can disable physics. Set the render to Halo.
Then you need to add an object that contains the area where you want the particles. Give that object an emission shader connected to the volume of the material, and add a Texture->Point Density node that uses the particle system of the icosphere. plug the density to the strength of the emission shader: