Although Roger at REAL considers himself the expert in this field, but as a quasi-expert, I like to look at signed LP albums. Especially from 60's-70's artists like Elton John, Billy Joel, Beach Boys, Neil Diamond, the Doors, Elvis Presley and anything Beatles. Unfortunately, those are also the most faked, Just look on eBay or websites like neautograph, autocentral.net or foreverlegends.com
For my current favorite, I have a Perry Cox authenticated Paul McCartney signed CD. I'm saving up for something signed by Elvis but authenticated Presley sigs are expensive, right Roger? His Elvis sigs starts at $1200.