Earphones problem with iPhone 3GS?

When I try to use earphones or an Aux.cord with my iPhone it doesn't work (no sound). The iPhone speakers work fine and there's no problem with the new earphones I purchased. What should I do?

Added (1). Yes the earphones fit perfectly.
It's the jack I think.

How to transfer songs to my iTunes?

I have an iPhone 4 and need to update to the 4S software. The problem is, the update deletes everything on your phone and I have songs that I downloaded from Napster! Those songs were on an old laptop which is now dead and the only way I can get to the songs is on my phone. How do I put the songs onto my computer? I have tried using "Transfer Purchases from My iPhone" and dragging the songs, but it doesn't seem to work.

How to print pictures straight from my iPhone?

I know stores like Walgreens Cvs and Walmart have printing machines where you put your SD card but the I phone does not have a SD card. Can I hook my USB cord to the machine and print my pictures straight from my camera roll?

Or does anyone know any other options I don't own a printer.

How to change from iPhone 4s to 4?

I recently bought an iPhone 4s and it has my number on it. I was wondering if there was a way I could change iPhones and put my number on the iPhone 4 that I already have because my mom is going to use the iPhone 4s. I was wondering if there was I way I could do this without going to the store. I have verizon if that matters

What website can i use to music on my iphone?

I have an iphone 4s and I've had it for a year and I want to finally put music on it but I don't want to pay for itunes…
what website is safe and free that I can use to put music on my phone?
also how do you use the website.

Added (1). Am I going to have download to my itunes first to be able to put it on my phone? And how do you do that if so?

Will my iphone use up data if?

I'm only using Wi-Fi? Does Wi-Fi prevent the use of data on the iphone for apps such as netflix, pandora radio, and others?