Good luck grinling!
I was job searching about 5 years ago, and am employed now.
As you go about looking for work, remember to have "more than one line in the water" at a time. More applications submitted will give you more opportunities and choices.
Since it has been a while, don't let the prospect of accepting a less-than-perfect job dissuade you from applying for a particular job. That less-than-perfect job could give you some needed experience, and may expose you to other job opportunities down the road. If you really like the manager at the place you mentioned, but don't get the job listed through the agency, keep in contact with that manger, let her/him know how interested you still are in working at that office/warehouse, and ask them to keep you in mind for other possible jobs. The next job they offer might not be listed with an agency.
If you have a network of friends, family, former co-workers etc. that may know employers in your field, let them know you are job hunting. In my experience, job opportunities often come through such networks.
Good luck, have patience, perseverance will pay off!