Level 80 - Contains various hints for the game. - http://www.level80.co.uk/psun.htm
Elfwood FanQuarter: fan art by Sarah Guilbeaux - Um Jammer Lammy fan art drawn by Sarah Guilbeaux. Mostly pictures of Teriyaki Ono, with a few of Lammy, Rammy and Parappa. - http://elfwood.lysator.liu.se/fanq/g/u/guilbeaux2/
Anime Lyrics: Um Jammer Lammy lyrics - Lyrics from the "Make it Sweet!" album, most of which come from the game itself. - http://www.animelyrics.com/game/umjammerlammy/
Neoseeker's Um Jammer Lammy Resources - Offers FAQs, screenshots, a discussion board, and links to reviews. - http://www.neoseeker.com/Games/Products/PSX/umjammerlammy/umjammerlammy_cheats.html
Whimsyload - Artwork by game artist Rodney Alan Greenblat - http://www.whimsyload.com/