Can any one suggest media to place add for staff

We are exhibiting at a show in Frankfurt and need a few workers for about a week to help on our stand. This is our first time to go to Frankfurt, I have already placed and add in Craigslist, but I feel in Germany this may not be the right place to look for workers.
the jobs are only temporary and require a combination of speaking English and German. 
Can any one suggest anywhere else I could advertise for staff to join us.

Craigslist is virtually unknown in Germany (as in most of the world).
The best known classified ads sites here are Quoka and Ebay Kleinanzeigen.
However, this kind of short-term job in Germany, if you want to do it legally, incurs social security and tax contributions to the authorities , for which you have to register as employer first. I doubt that the effort is worth it. Therefore you better engage a third party service provider to temporarily send you some of their people. The trade fair organisers can give you contact details of suitable service providers.