I've sold a few indie features. Yes, you want release forms from everyone that contributes something recognizable, including your storyboard and conceptual artist. Get a release for all actors, your director of photography, visual effects guys, people who make original sound effects and music for you, the writer - basically anybody who can point to a scene and say, "I did that." or "That's me."
Trust me, people get serious, when they didn't think the project would go anywhere and then it gets picked up. I had one person threatening to sue, because their name didn't appear in the credits on the distributor's box cover. Fortunately the credit was prominent in the movie, itself. Save yourself an arguement or legal issue and get a release that says you can use their work on anything having to do with the movie, including documentaries, music videos, and anything promoting the project.
I usually shoot on private property; if the property is used prominently and is owned by somebody else, get a location release. If there is artwork on the wall, get permission from the artist to use it. If there is incidental music playing in the background, get permission.
It's funny, how this has changed over the years. When I sold my first feature, in 1990, no one was asking for DP or Visual Effects releases. I wrote, produced and scored the movie, so I just needed actor releases, in addition.
A lot of distributors demand Errors and Omissions insurance, these days.
You can get releases, on the net.
Sonnyboo's site is a good place to start: