idea: attach rope/cord to frames, and hang from what looks like a series of small hooks on a painted 2x4. alternately: hang from a curtain rod so frames can be rearranged more easily. Nadia Geller's Downtown Design Studio Workspace Tour
Gallery Wall! LOVE! This website also has great design templates! Start with hanging up paper on the all that is the same size as your picture frames. This way you can experiment with different layouts and see what you like best.