They are fabulous pets! I’ve had around 40 over the years. I’ve been involved in rescue, fostered babies etc.
Definitely look at rescues and shelters for piggies. Piggy rescues in particular will be helpful and will have a better understanding of the needs of the specific pigs you’ looking at.
I’ve had males and females. In terms of friendliness and sociability I’ve never found one sex to be preferable to the other. Boys are perhaps marginally more smelly but it is minimal.
Keep them indoors, don’t use newspaper. You can bed them on fleece which I find more cost effective in the long run and not stinky. The bigger the cage, the more interactive they’ll be. They are have their own personalities, some love cuddles, others don’t. They will become experts at hearing you open the fridge door!
The Cavy Savvy Guinea Pig Community on Facebook is a good starting point. Also look up guinea pig rescues as they usually have some great info. Plus they often post photos of baby piggies for you to coo over! I don’t support active breeding when so many end up in rescue or shelters, but baby piggies are possibly the cutest animals in the world!
The guinea pig cages store and guinea pig fleece store on the web are American, but will give you some ideas about cages and bedding.
If you decide they’re for you, you will have your heart stolen very quickly! I love all animals and am involved in shelter work, mostly with dogs, but piggies will always have a special place in my heart.