has a free online version that'll help you calculate your hops using their recipe generator. only downside to free version is you only get to save 1 recipe at a time.
since different crops have different alpha acid levels, plus the variance due to boil volume (or rather, wort gravity hindering utilization), its just easier to use a calculator.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10