Create a Sorceress, then max out her Firewall. Trade some items for a good Tarnhelm, some ChaceGuards, and other +% to Magic Find items. You Sorceress should be at about level 45. Then, go to Channel Cows/Cowz and wait for someone to make a game. Join that game and Firewall all the cows. Your experience will increase and you will get unique items. Do not duel or do anything dangerous with this sorceress, as you will get killed.
Get any item
Use the following trick to get almost any desiered item. Go to the person in your highest Act that gambles (for exampel, Gheed or Jamella). Go to gamble. A list of good items will appear. If you do not see anything desirable, exit, then go to gamble again. There will be a new list of items for sale. Repeat the process until you have found what you want.
More experience
Join a Battle.net or other multi-player game and join a party. You and your partner will share experience. The more people in the party, the more experience everyone gets.
More money for items
The easiest way to increase the value of an item is to have it identified by a Identify Scroll or by Deckard Cain. The value will immediately increase.
Secret Cow level
Defeat Baal under the same difficulty setting that you are making the cow level in. Take Wirt's Leg (found in Tristram) and a Tome Of Town Portals and put them in the Horadric Cube. You must transmute them in Act 1.