Call them from a different number, and have them call you back on a different number. That way they won't know whom is calling, and they won't have their notes right in front of them. Bill is right though, satellite is slow, but if you can't get a dial tone on your phone, what other choice do you really have? I would try to stress to the phone company that your landline and internet are crucial for you to work. Tell them you can't send faxes half the time.
That's a bad predicament.