Big Sunday — the 20-plus-year volunteer group based just north of Hancock Park and west of Larchmont Village — is looking for a new home. “Our lease is up at the end of the year,” David Levinson, Big Sunday founder and executive director, told us. Levinson is looking for a new site for the group’s headquarters with equal capacity of about 4,000 square feet for office, event and warehouse spaces. “We’re excited about the many possibilities and opportunities — which might, this go-round, even include parking space!” Many of the group’s 2,000-annual ways for people to help others take place at schools, homeless shelters and at its Melrose headquarters.