There are tons of Voip providers in the world. Your question didn't specify which country you are located in, so here is a list of Voip providers by country: http://www.voipproviderslist.com/. Just scroll down and select the appropriate country.
That depends on your mobile phone service provider, your e-mail service provider, and/or the make and model of your phone.
The phone will work with any home phone provider such as Sprint or AT&T.
You will need to take your phone into your service provider to determine why it doesn't get signal any longer.
If you mean that you have a phone service which has the wrong area code in its number, you need to contact your phone service provider to get it changed.
You would need a court order and then contact their service provider.
Ebay is good to purchase a phone, but you will still need a service provider. With bundled purchases you need to know what provider's SIM is included.
The only way to unlock a phone that you found that has no service and it has a code is to obtain an unlock code from the phone's service provider. The service provider may charge a fee for unlocking the phone.
There is usually no need to have a landline phone to obtain internet service. Any internet service provider in your area can discuss wireless or cable internet with you.
Perhaps it is 'locked'. You will need to call the service provider or the place that you bought it from.
You would need to contact your service provider - and ask them for a new number.
When your cell phone is unlocked, you can use it with any service provider's network. The original service provider will have to unlock the cell phone for you.
When looking to get a new cell phone, you will find that you will have plenty of service providers to choose from. As you are choosing a new phone service provider to go with, you should select one that has a reputation for good customer service. A phone service provider should be able to work with you in events of phone malfunction or improper billing. If you read consumer reviews that state otherwise, you should choose a different provider.