I get calls during the day as well. I teach kindergarten and there is no way I can take calls while teaching. Like Leah, my phone is on mute. I use Google Voice and my message goes something like this (I think). "Thank you for calling Brenda Bakes. I cannot come to the phone right now, but please leave a detailed message and I will return your call within 24 hours. You may also contact me through email at blah @ blah blah. Please keep in mind that two weeks notice is required for all custom cake orders. Thank you for calling and have a great day."
If they leave a message, they get a return call. If not, there is not much I can do about it.