"There's going to be something for everybody," she said.
"You can't really lose," Wittman added.
Riggio said the concert will be mostly acoustic and have many different instruments.
"The first group is a salad of vocal harmony, mandolin, banjo, guitar and possibly a didgeridoo," she said.
She explained that the didgeridoo is an instrument from Australia that requires breathing in the nose and out the mouth at the same time into a large tube. Riggio herself is the second act.
"What makes Gina [Riggio] awesome is that she's original," Wittman said. "She's impressive because she writes, sings and plays piano. She does it all."
The third and final act will be Penn State graduate Dean Blackstock and Eric Goeller (senior-psychology), an acoustic guitar duo that has been together since last spring.
Goeller calls their style "original acoustic," and Blackstock calls it "experimental folk."
"We're just trying to convey our thoughts and feelings that we've developed over the year into the music, and the atmosphere created by the acoustics and the crowd," Goeller said. "I wished I could be involved in something for others, and music is the way I hope that can happen."
Though the concert is free, the musicians are accepting donations, which will go to Eco-Action and its projects Kyoto Now! and Earth Day.
Riggio said she had high hopes for this year's concert.
"We had a pretty thin crowd last year, but we made $80, which was pretty good," she said. "I hope people can find it in their hearts to come, and to donate. Even quarters add up."
Webster's owner Elaine Meder-Wilgus said the store is planning to donate a percentage of tomorrow's sales.
"The money goes to education and awareness, of both the organization and cause," she said.
"We can do a lot as individuals. We don't have to move mountains to make a difference," Meder-Wilgus added.