We have a FaceBook group for collaborations between UIUC Dance and Music students. Please join this group.
Composers Forum article “Commissioning by Individuals” answers basic information about commissioning a custom score.
New Music USA has some information on how to commission music. Search the site for the latest blog posts relating to the topic.
And if you search “how do I commission a piece of music?” on Google, you will get a LOT of hits on the subject, many by composers offering their services.