If you don't have data, there are FREE calling and texting apps out there that you can use
Magic Jack - you can make phone calls (outbound) over 3G or Wifi, but for someone to call you, its a little complicated. They've got to dial a 1800 number and enter a complicated number with astericks and things.. Call quality is pretty good.
TextPlus - texts are free, but you have to buy minutes or watch videos for calls. You can also call other people with the app for free as well.
GoogleVoice - texts free
Skype, Quik, etc. - free calls to people with the app.. video calls not supported on LG Optimus S
I hope some of these apps helped. I use TextPlus for texts and MagicJack for calls on my iPad itself when I need to get ahold of someone without an iPod, iPhone, or iPad...