Here's a nice list of Alternative energy stocks, ETFs & mutual funds
from cutoilimports.com. Although there are a lot of stocks on the list, most are unprofitable and specualtive at best. However there are some good ones like ADM, Ormat Tech, Evergreen Solar, and MPGI. A great way to play these alternative energy companies is of course mutual funds and PowerShares WilderHill Clean Energy ETF (PBW).