I have a scene in my film where there are two photos of famous people. I'm wondering who would I contact to get a release. The Photographer or the person in the photo. Or would I need a release at all.

Most likely both, and YES... The photo is likely copyrighted, and the use of the "likeness" is probably also protected...

Any options for using "stand-ins" or made up celebs? Probably faster to make up some posters/pictures than get clearances.

If you already have shot the scenes then you will need to get permission. If you have yet to shoot the scene then take a look at getting a royalty-free photo from the a service like Stock Photos | Shutterstock: Royalty-Free Subscription Stock Photography & Vector Art (http://www.shutterstock.com) Any necessary model releases are included. The costs are very modest although there are some limitations to the license e.g.

In multimedia presentations and incorporated into film and video for television and/or internet broadcast, and theatrical display only where the intended audience will consist of fewer than two hundred fifty thousand (250,000) viewers;

Thanks guys for all the input I really appreciate it.