don't hear back within a day or so, move on to the next provider on your list.

I always require that a gentlemen leave a message with a name, callback number & time frame that I can call him back... if all that is not in the message, they will not get a return call. And please, don't call a provider every hours, 4-5 hours in a row... if she hasn't called back/answered by then, she probably has prior engagements. There have been many instances where I have 3-5 missed calls after a 2-hr appointment, but not one person has left all  the needed info... or the guy that called 7 times in 1 hour(those NEVER get call backs, and if this behavior continues, they go on a do not see list).

Also, if she has a calendar on her website, make sure she's even available during the day and hours you're trying to call. I get plenty of calls after midnight, even though I don't work past 12, and those guys never get callbacks the next morning, unless the left detailed call back instructions.