Ok, another question. Lets say I have a lovely shot of a road, but the camera I’m holding is very shaky. this makes it a pain to animate in 3D and not have the 3D object sliding around the flat plane movie. is there anyway I can map the movement of the camera in the live action shot to the 3D camera in blender?
Yeah, sure is.
You can have a look for Icarus & Voodoo in the way of freebies. There’s also SynthEyes, PFTrack and my personal favorite, BouJou4.
Voodoo is the one I’d recommend. Icarus is older, (I believe no longer supported) & I’ve found generally harder to find to download and then hard to use.
I use Icarus, and while it is no longer supported, it works quite well unless there is excessive camera movement and tracking features move a considerable distance between frames (even high-end trackers still sometimes have that problem, but instead they display helpful error messages… 
). For me, there wasn’t a choice between Voodoo and Icarus because only Icarus works on a Mac.
Icarus and the Python script that imports the tracking data into Blender can be downloaded here. The page also has some video tutorials on using Icarus with Blender and Adobe After Effects. The official page for Voodoo can be found here.
As to how Voodoo and Icarus compare, I can’t say (from doing a Google search it seems to vary from person to person). As enhzflep says, Voodoo is attractive because it is still supported (and it also has a Blender export script built-in), but don’t let that put you off Icarus either…
Steve