Hops are naturally bacteria free. There's no need to sanitize them.
As for an IPA...how many do you have? Are you using them fresh from the vine or pre-dried and frozen? I'd suggest using your cascades for dryhopping. The nuggets and magnum are higher AAU's, and since you don't know how high, you don't want to get too much. Unless you're one of those people who think there's never "too much" when it comes to hops.
Keep in mind, if you're using fresh from the vine hops, you need about 5-6 times as many as you would use normally. So, normally I dry hop my IPA's with about 2 oz. of cascade (or whatever else I'm feeling into). So, I would dryhop with 10-12oz of fresh hops. I wouldn't suggest using fresh hops though because you'll probably get a very grassy flavor.
Dry them and then use them how you normally would use storebought hops.