Short-Haircut.com and Hairstyle Stars feature pictures of retro haircuts. Both sites have a variety of haircuts that were popular in the past, such as bobs, beehives and quiffs.
Short-Haircut.com has images of classic celebrities sporting retro haircuts and focuses on shorter styles. There are also some images of modern celebrities wearing retro styles that are popular as of 2015.
Hairstyle Stars has multiple pages about retro haircuts with pictures. Each page focuses on one or a few hairstyles and gives ample information for recreating them, such as product and tool recommendations and multiple celebrity examples for reference when styling hair.