for beginners, you could try using youtube as a reference. ie, searching for "hip hop samples" or "oldies, blues,soul" etc. Obviously, the samples on youtube have been ripped several times so beware of what you cut up. to me, its a matter of POV on a sample (look "Circulate" by J.Dilla vS 9th Wonder's "Let The Dollar Circulate" 2 different versions of the same song by Billy Paul)
you could also go to a record store (not sure if you have a record player) and just jot down names and groups for reference. heck, you not want to delve into the blues/jazz/soul like most producers start off (imo), and go into a totally different genre of music..sampling is cool but playing your own music is special
some producers can flip a sample so well that when they re-arrange it, it sounds like a totally different sound/genre than what the next guy would go after...it really takes a great ear (an art) to do this (a la Dilla, Madlib, Kanye, Flying Lotus, etc)
hope this helps ya man..good luck and start diggin!!
It's called gracious professionalism. The idea is to be open and help more people learn.
ya know?