The Maine Forest Service is who you should contact. If you can get a close up, clear picture of the pest and any damage that is occurring, that can be submitted and is helpful to confirm what pest is there and potential actions you can take. In some cases, MFS personnel can come to the property to discuss an infestation and what might be done to limit damage.
Specific information from MFS related to spruce budworm can be found here.
You may submit a sample of insects and diseases that are affecting your trees to the MFS, along with a description of the damage. Please use their on-line reporting form when you submit a sample. Mike Parisio is the lead MFS entomologist for SBW, contact info:
Mike Parisio, Forest Entomologist, Augusta
Maine Forest Service
[POSTAL] 168 State House Station
[PHYSICAL] 90 Blossom Lane
Augusta, ME 04333