I have been casually looking for a new job, in hopes of getting rid of my commute. I started working with a recruiting agency, but they are asking for managerial references up front and have said that coworkers are not sufficient. This is my first job out of college; I don't even have contact information for managers from before college; and I'd rather not alert my current employer that I am looking for a new job, since I'm not set on leaving (going to take a lot to replace the benefits here).
Do others use recruiting agencies? Should I just look for a job without one?
What should I do regarding this reference request?