How to transfer a song to my Iphone 4s?

How do i transfer a single song to my iphone? I have a PC. I downloaded some songs from youtube and put them in my music folder on my computer, I have also got itunes. But i can't seem to be able to transfer a single song on it's own?

Which laptop should I buy for programming and minimal gaming?

As mentioned in the title, I'm looking to buy a new laptop soon (possibly within the next year or so). I've been a PC (Windows/Linux) user all my life, but after seeing all the attention that Macs are getting (mainly amongst fellow computer programmers),

I started doing some research and asking around. I found that Macs run on the *nix system, which I very much like from my Linux experience. I also know they don't get as many viruses, and from what I understand are the only systems that can develop iOS apps. I own an iPhone, and plan on staying an iPhone user for years to come, so being able to make apps would be nice. I also know that Apple makes both the hardware, and the software for the machine, which can explain why it runs so well. These are all pluses in my book.

I've always known that gaming was not Mac's strong suit, and thus have always discarded them from the pool of options when buying a computer. However, nowadays the only games I really play are Counter Strike: GO and League of Legends. I'm pretty sure a Mac can handle those, as they are not very powerful games. I also liked playing Skyrim for some time, but I can live without it, so it shouldn't make or break the choice of my next laptop.

Ideally, I wouldn't want to pay more than $1300. I'm considering a 13" MBA or 13" MBP. 256GB HD would suffice with 8gigs of ram. What would you all recommend? Especially with processors and screens (which I know nothing about).

Added (1). Also I forgot to mention, I currently own a Lenovo Y580. A desktop replacement because I really don't think my needs require one. The Y580 is nice, but probably too powerful for my needs. It's also unnecessarily clunky/heavy. It worked well for the first year, and started bugging out this passed year. I had to send it in 3 times for a new hard drive. I'm not saying a Mac would be perfect, but I'm willing to give it a try.

P.S. Advice on Iris graphics vs HD 5000 would be appreciated.

Where can I get plain white iphone cases?

What is a website where I can fine plain white plastic iphone cases for iphone 5 and 5S. They need to be not too expensive and able to buy in bulk because I'm going to customize them and re-sell them.

IPhone 5s and 5c cameras in comparison to the 4s camera?

I own an iPhone 4s. The camera is pretty wonderful aside from the front-facing camera, but I improve those photos with an app I bought. So I was wondering, for those of you who are experienced iPhone users, if the 5c or 5s iPhones had a better camera than the 4s I'm currently using?!

Can prepaid iPhone 4S have personal hotspot?

I recently got an iPhone 4S on prepaid vodafone and I read on the web that you don't get personal hotspot on prepaid IPhone's and I just got a prepaid iphone so I'm wondering if vodafone added a new thing.