Absolutely, I am assuming that you are talking about the bottom bracket spindle, you can buy replacements, just make sure it is the same length and that the ends are the same shape (probably a square taper)

Here is a link to what I am talking about:
http://sheldonbrown.com/harris/botto...ets.html#axles

while you are at it, it wouldn't hurt to inspect the bottom bracket cups and the bearings to make sure the impact did not affect them.

If you broke the crank arm, those are also abundant, just make sure the new crankset is compatible with your bike.

Matt