One thing I did when I started Pt/Pd was to buy some prints from people I considered to be master printers. These became my reference prints. Not only do they look good on the wall, but they're inspirational too. When I struggle and get frustrated, I can get them out and remind myself what's really possible (and how much I've improved since I started ). Good prints from top printers are not cheap but they're worth the investment.
I'd recommend this to anyone who is thinking of starting contact printing (or any kind of printing I suppose). Just make sure they're in the same medium that you want to work in. Obviously there's no point in comparing a master printer's Azo print with one made on enlarging paper, or a pt/pd print with a silver print. They're different media, so are unlikely to be very helpful as educational tools.