Does anyone know if there is some type of phone service provider(s) or some sort of software package that changes a person's phone number for every call? For example, I rec'd a call from 555-1212 but did not answer...less than 30sec to a minute later my phone rings again w/a different #, then again w/a different#, and all of a sudden, I would stop receiving calls all together for a while.  Does anyone know if this can be true that someone can call u with different numbers that show up for caller id purposes???

Yes, such things do exist and are used by telemarketers.

555-1212 is a general information number... just insert whatever area code you have in front of it and it becomes essentially 411.

There are such things as Spoof and you can buy minutes like a caling card and enter any number

Years ago when I first started in the hobby I did not have a cell phone. One provider asked why my phone number kept on changing when I called her, it was the calling card company.

But she has a number caliing from 555-1212..http://www.spoofcard.com/ .. This might help you.