Ah, so you'd like a case a case where a party attempted to absolve blame for death or personal injury owing to the contractual clause? There aren't many cases on the issue directly, because the legislation is so clear on the matter and it would take a very incompetent person to draft such a contractual clause. However, the stupid are everywhere.
Try starting with Thornton v Shoe Lane Parking or Spurling v Bradshaw and read Lord Denning's dicta, which deals with the reasonableness of clauses. Then try Phillips Products Ltd. v Hyland, where a company aimed to move the burden of compensation onto another person. I would also read Stag Line Ltd. v Tyne Ship Repair Group and in particulare LJ Orr's thoughts on limiting liability (rather than excluding it.) Full citations:
Thornton: [1971] QB 163
Spurling: [1956] 2 All ER 121
Phillips: [1987] 2 All ER 620
Stag Line: [1984] 2 Lloyd's Rep 211
Any other questions, just ask.