I use BA, minorleagueball, Project prospect, Mound Talk, Baseball Prospectus, milb.com, Diamond Cutter, Get Sports Info, CBS, Sports Illustrated and the baseball cube and virtually every team specific page or blog that you can think of, among others...
This is very late in the draft... There are currently over 180 minor leaguers taken, so no, there aren't better arms available than these guys... The only other pitcher that comes close for me is Deolis Guerra and maybe Brett Sinkbeil.
So, if the new list is:
Brett Sinkbeil (doesn't K enough for me to think he'll succeed at the major league level).
Who do you choose now?