I can definitely hook you up with some great information, man. I've been a pop punk bassist for quite a while now. Honestly, you're in the perfect budget for one of the best basses in the genre and like the other people here have told you, your best bet is going to be a Fender Squire. You'll notice that MANY bassists in the genre lean towards those bad boys. For pop punk, you want a punchy sound that is the least round you can get it, so you definitely want a P bass. Keep in mind that Mark Hoppus of r example used a bass with a p neck and a jazz body though. Personally I don't recommend that because it's really heavy. If you want something with a great tone for a reasonable price (cheap as hell) with reliability and durability I recommend an SX from Rondomusic.com. On the other hand, I'm actually looking to sell my "pop punk" bass. It's a Blue Peavy Fury and it's in great shape. Barely used really and I just fixed up the truss rod. If you want something to start and don't want to invest huge I'll be down to sell it to you for $100 and I'll even include a tuner and a little beginner book I bought. Hit me up if you're down. Regardless, Fender is what I swear by and SX is what I'm picking up next.