I've found a number of how-tos for solving video but I'm just looking to put an element in a photo and can't seem to find a how-to for that. Is it possible in blender to do a camera solve with a still image? Thanks.
There is an addon called BLAM: Camera Calibration Toolkit it can be used to match geometry to still images.
It uses the grease pencil to determine the perspective and focal length, and has tools for geometry reconstruction.
see http://stuffmatic.com/blam-blender-camera-calibration-toolkit/ It can be downloaded here: http://stuffmatic.github.io/
UPDATE: Blam is no longer mantained and has been replaced by fspy:
For a detailed post on how to use blam and Fspy read: How can I recreate geometry using a photograph?