I use The Recipator for estimating gravity, IBUs, and color. This tool provides general ranges for various styles, including IPAs. You should notice the style guidelines for IPA top out at about 7.5% ABV. If you want something a little stronger you'll need to add some extra fermentables and I'd recommend boosting the IBUs in the same proportion. (I.e., if you bump your OG up to 1.080-1.090, you'll also want to bump IBUs to 70-75 or so.)
BYO has a great hops guide for picking varieties appropriate styles. If the hop you pick isn't available on Recipator, no worries, just pick any hop in Recipator plug in the hop's AA rating into the form.
I also recommend Ray Daniels' book, "Designing Great Beers." It provides some excellent information about which grains and hops are commonly used in a wide variety of beer styles for both commercial and homebrew recipes.