The BBC have refurbed the official tie-in video game to Douglas Adams' beyond-seminal radio comedy show and are hosting the new version, murderous paradoxes, spit, polish and all, on their website.
You can also listen to the first episode of the show on the new iPlayer, too, though you'll find it only of the most minimal help if you're looking for hints with the game's sadistic puzzles and booby trapped plot lines.
Really, the only way to beat the Guide game is to save. Regularly. I'd recommend you save very time you accomplish anything. And restore every time you die. For a hundred lives or more.
"Bastard hard," I think, is the phrase I'm looking for. So good luck – and don't forget your towel.