What once was old, is new again...
~ Recycled matte, uncoated paper is one of our favorite looks and feels for starting the "old" appearance.
~ Distressed features can be added in the artwork (use scans of distressed paper), or by adding effects such as spot gloss applied to newer areas, and not applied to "worn" areas. Be sure to continue the effect across the inside spines (PIPS or reverse inside printing) so the illusion is kept up.
~ Using embossing or debossing can give an item a distressed and "dented" look.
~ Consider antique photo corners for old images.
~ Sepia tones are usually simulated in process color and are ideal for WWI or WWII imagery.

If you don't want to go too old, retro can be achieved by features like book binding (chipboard covered with a paper wrap) on the old vinyl LPs. Or earlier yet, like the 78 style sleeves (swinging sleeves). For retro on a budget, may we suggest some inner sleeves (colors like parchment, or printed 1C or 4C) for the discs, and just using a thick stock with pockets opening to the outside.

If you have a photo of something you like the look of, we can help you determine what features we can incorporate in your project. We'll be happy to make suggestions for paper stock and special effects to help achieve that look.