Crate training, absolutely. Just make sure it's not too big. You don't want the pup to be able to escape his mess.
If he's going potty every 20-30 minutes, there is a problem. Puppies have to go a lot, but not that often, unless they're drinking a lot of water. Check with your vet to rule out a medical problem.
Puppies will try to drink the entire bowl of water, so do supervise him when he drinks.
Most importantly, be on him like a hawk every second he is out of his crate. The SECOND he starts sniffing around like he might be ready to pee, scoop him up and rush him outside.
Also crucial--when he pees outside PRAISE! I mean over the top, berserk, neighbors think your nuts level praise. And you do it WHILE he's peeing, not after. Puppy attention spans are short. You can use treats, too if you wish.
These techniques work.
I've done it more times than I can count and I've got a nine week old puppy in the house right now.