The Massachusetts Emergency Management Agency has some useful resources if you need help, or if you want to help out:
For crisis counseling, please call 1-800-985-5990 or the City of Boston Health Line at 617-534-5050. The American Red Cross has material on their website about emotional recovery.
If you have a tip, call 1-800-CALL-FBI (225-5324) and choose prompt #3, or email Boston@ic.fbi.gov.
To make a donation, please visit www.onefundboston.org.