@sangre you should look into Hopville.com
I wanted to brew this to take to the beach in a few weeks, but the original recipe comes out over 7% abv, and I wanted something a little less strong so it's more of a session beer. So I plugged in the original recipe to see how it would turn out (alcohol content, color, bitterness, etc) and then started modifying things to see if I could brew a similar beer that's closer to 6% abv (since that's what the original is, too).
Here's what I came up with:
http://hopville.com/recipe/815655/american-ipa-recipes/dogfish-head-60-minute-ipa-clone
My LHBS recommended that I should use Ringwood as the yeast, since that's what Dogfish Head uses, so I thought I'd give it a shot. My OG was spot on with what hopville said it would be, and after 12 days fermenting, my FG was also spot on. I'm going to check again tonight and if it hasn't moved I'll start dry-hopping.
But anyway, tools like hopville, beer smith, etc. will allow you to mess around with a recipe to see how changes/substitutions will affect the end result.