I have found this great tutorial for creating retro graphic artwork via the Flickr site of a fellow event photographer Helen.
There are a lot more tutorials for graphics design like this on this website called
Abduzeedo. The particular one that shows how to do the picture above can be found here: Retro Geometric Vectors in Space with Illustrator and Photoshop.
Artwork by Aloa from Abduzeedo
The tutorial and design is created by Aloa, one of the Abduzeedo writers. Personally, I find these tutorials quite inspiring. Studio 54 and the seventies live! Unfortunately, the guy uses relatively expensive commercial tools to create the designs, but you should be able to achieve similar results using free (open source) software like Inkscape and GIMP. Both are available for Linux, MacOS and Windows.
Hope that we'll see more event advertisements of this kind again in the near future!