Info. wanted on wrecks to snorkel in Door County

[AandA]

Thanks so much for all the great information!  ;D Is the Door County Shore Diving Guide only available from Green Bay Scuba? Can it be ordered online as I doubt very much we'll get to Green Bay. Also, I'm a scuba diver and have a wet suit but my friends are not. Is snorkeling possible without a wetsuit-in other words about what will the surface temps be in mid-July?  ??? Another option would be for my friends to rent a wetsuit if there is a convenient scuba shop somewhere in Door County. Again, any suggestions are very welcome! 

Alyson