I prefer pm,email, or text, if I have screened you and your coming and need to call I dont mind to much but dont prefer it, unless I have seen you before then I dont mind a call at all.
If you have an appt and the girls not answering text and your waiting outside, then I say blow her phone up, not fair to put your self at risk looking weird sitting outside waiting, but again thats if she hasnt answered your text back.