Here's a list of guys off the top of my head. I haven't included teams with a young closer who figures to keep the role through 2008 (Orioles - Ray, Blue Jays - Ryan, White Sox - Jenks, Angels - K-Rod, etc.). Of course, this is by no means a complete list, but should fit the bill well, I hope.
Atlanta Braves - Joey Devine/Anthony Larew
Arizona Diamondbacks - Brandon Medders/Tony Pena
Boston Red Sox - Craig Hansen (if Papelbon returns to SP role)
Chicago Cubs - Kerry Wood
Cincinnati Reds - Bill Bray/Grant Balfour
Cleveland Indians - Fernando Cabrera/Fausto Carmona/Brian Sikorski
Colorado Rockies - Ramon Ramirez
Florida Marlins - Taylor Tankersley/Logan Kensing
Los Angeles Dodgers - Jonathon Broxton
Milwaukee Brewers - Jose Capellan
Pittsburgh Pirates - Matt Capps
San Diego Padres - Scott Cassidy
San Francisco Giants - Brian Wilson
Seattle Mariners - Rafael Soriano
St. Louis Cardinals - Adam Wainwright
Tampa Bay Devil Rays - Seth McClung/Edwin Jackson/Chad Orvella/Juan Salas