To look for an internship, use the same basic steps as you would for a full time job. You will find that most jobs sites have internship positions, you just need to know where to look. Below are links relevant to all majors.
Lasell College Central Network
All majors – has opportunities specifically for Lasell students
Chamber Intern Connect
Arts and Cultural Organizations
One Search All Jobs (All majors)
Greater Boston Chamber of Commerce
The sites below have some internship/job information, but are more resources to learn about the industry.