The Sims 2 Tips

Quick Tips
Mission Given By: Ava Cadavra
Finding the Pyramid
To find the pyramid, go to the desert (after 9 pm) and look on all of the sand dunes. On one of them there should be a small pyramid. Don't worry if it is small, it is supposed to be. Go up to it and choose 'Investigate' or whatever it says (I forgot haha). Then, a mummy should pop out. I forgot his name, but talk to him.

Mission Given By: Frankie Fusilli
Finding the Bars
First, you must buy the metal detector at the store. It is about 800 simoleons. Then, go into the desert and use it. When it beeps, use the thing on the right side to make the item clear. If it looks like a bar with a little tiny sign in the middle, touch the shovel (dig). Find three of the bars (any) and talk to Frankie Fusilli.

Mission Given By: Ava Cadavra
Finding the Mystic Cowbell
To find the Mystic Cowbell (yeah, I know, stupid name, and who says it's 'Mystic'?) just go up to the cows in Strangetown. One of them should have an option, when up close, to 'Take Cowbell'. Choose it, and talk to Ava Cadavra.

I think, the easiest way to make money is to play Keelhaulin'. But, you can also:
Find gourds and sell them at the Saloon
Find nuclear rods and sell them at the City Hall
Use your metal detector (if you have one) and find items in the desert.
Calm down, cheer up, or restrain other sims to earn money, gourds, or nuclear fuel rods.
Find missing items from other sims' hotel rooms.
Vanquish aliens.
(One of my favorite) Use the vacuum and find items in the vacuum (some things are not worth money such as gumball, eraser, etc.) (things that are worth a LOT are glowing rock, golf ball (rare), action figures, etc.)
I think that's about it, or at least all I can think of at the moment. Hope this helped!