Kurt Carr is good - "In The Sanctuary" is simple enough for our praise team to do.
Joan Hall has a list of non-solo songs on her Choir site -
http://www.squidoo.com/joan-alexander-hallOur choir recently did 'Great Things' by Ken Reynolds.
Others -
Ricky Dillard - "God is Great"
Bishop Morton - "Chasing After You"
Reed's Temple Choir - "Oh, What He's Done For Me"
"My Soul Cries Out"
All these can be done without lead singers.
BTW, these are all faster songs - IMO beginning singers and choirs can pull them off better than the slower ones...