We live in a new age of technology and lucky for you there's millions of ways to connect. It just depends what your after. Just to name a few.
IMessages (green app on home screen) this will contact other iPad, iPhone, iPod etc users. Check your details for this in settings.
VoIP calls - things like Skype etc are great ways to connect and are available on iPad.
Email - many users now have this set up directly to their phone.
Social media networks have messenger facilities like Facebook
There is a tonne of websites online offering to send a free text
If your an O2 customer you get 10 free text through their website.
I won't list all of them now
but the app I use to make calls and text directly from my iPad is Truphone app, top it up with credit and you don't even need a headset just talk into your iPad. Can also text from this and I think it's cheaper than Skype and many other providers.