Hi,
First you'll need a CPH number before you buy anything livestock wise.
You're best to buy from a breeder - depending on what breed you're looking for there may or may not be someone near you, maybe even someone on the forum ?
Don't buy just 1 pig, they're very social animals and will get depressed on their own - you need at least 2.
I can recommend "Starting with Pigs" by Andy Case as a good book to give you the basics.
Lots of learning to do first though

Good luck,
Karen