Tips:
Do not distribute your exp. points evenly. Concentrate on the abilities that will help your character. Magic for Sorcerors, Dexterity for Rouges, and Strength for Warriors. Remember to always put some towards VITALITY!
Make sure you use each character class to your advantage. If your a Sorceror don't go around trying to act like a Warrior using a sword and building up your strength. Make use of your spells and magic abilities. If you are a Warrior don't go around trying to cast spells, build up your strength and vitality. A Rouge is not meant for close combat, stick with the bow and arrows, and build up your dexterity and vitality.
Be careful of PK's. A good number of people on Battle.net are willing to help you out. But if it seems too good to be true it probably is.
Downloads:
Raymond's Diablo/Hellfire Trainer this awsome trainer supports V1.0, V1.4, Hellfire V1.00, V1.00a, and V1.01 enjoy this is a great one!
Mandrak Diablo Trainer/Item Editor this well done editor supports V1.0 and V1.4 of Diablo
Here is the latest patch to update Diablo to Version 1.04 