Korn...
Your phone has to be digital and not analog. Most of the phones nowadays come with both. You just don't see many analog phones being manufactured due to the low cost of transmitting digital signalss. Your mobile phone service must offer short messaging service in order for your phone to work. Most carriers are offering the service.
I'd suggest you go with a Nokia phone if you have a choice. I just bought a Nokia 7160, and I love it! Much much better than the Motorola Timeport I had. It is also much better than the Motorola Star Tac. You'll get much better results with the Nokia batteries vs. the Motorolas. The 7160 has a rather large screen which makes it easy to read messages. The Motorola screen is tiny and is hell trying to read messages and emails. The Nokia cost me about $100 bucks and it's worth every dollar.
My plan consists of: NO LONG DISTANCE which means no roaming, 450 minutes per month, voice mail, caller ID, call forwarding, and 50 free messages. After that, they are .10 cents a piece. All this for $42.95....