I contacted an agency last week. After a couple of emails I was directed to their web site. Filled out my contact info and received an email booking an appointment for next week. Then I got another email asking for my work number. This happened on Wed. The booking said that the provider would contact me but nothing so far. It's been 72 hours since I got that booking email.

Should I drop the agency an email tomorrow asking what's up? The appointment is scheduled for Tues and I need to know.

I should also mention that I have no references, though the agency didn't say anything about that....

... seriously, I don't know of any agency that books a week out unless it's the customer's choice.  Go find a reputable Indie and explain your situation.  I'm sure it can be worked out.

It was my choice to book early. Are you saying you think I gave out too much info by giving my work #? Provider is well reviewed here.

Stay away from agencies ... go with a well-reviewed independent

This is a popular opinion young Grasshopper, and one you will need to consider and decide for yourself.  Quality agencies exist in many cities, though they are outnumbered on the whole by those which are lacking.  Still why limit your possibilities by prejustice.

I was in your situation a couple of years ago.  I took a four day vacation in Seattle, and lined-up visits with a top indy and a reliable.  Everything with the indy went smoothly, but I never heard back from the agency.  On a lark I them on the morning of the day I had requested, and they said sure, she will be there!  Well, she arrived late, she was stopped for speeding and had the citation in hand to prove it, but the gal I requested did finally show up, and we had a great time.

Turns out I was worried about nothing. The agency contacted me today to confirm my appointment this evening. I was actually out of town today and asked if I could push the appointment back 1 hour. No problem. Things went very smoothly from there. Had a great experience with a great provider who made a nervous newbie feel very relaxed and confident.

Alls well that ends well!