Drop down lists by location in Tickets

I was wondering if there is a way to get better information from our customers in terms of printers.

Currently we manage over a 100 different printers at 14 different sites. People often create tickets that they have issues with the printer but never give us the info on which printer they are having problems with.

Our ticket currently just has a box where they enter in information. We also have highlighted text telling them to enter in the ID of the printer so we can effectively resolve the issue. Often times people ignore the highlighted text and we often have to contact them to get the information we need.

Is there a way to integrate a drop down box that only lists the printers they have by location? and make it a requirement? so if they don't select a printer, they can't submit the ticket.

Thanks.