The Scatterbrained Sorcerer Quest
5350 gp and 10650 experience. *Please note this is a longer quest than most but I think this quest is easy for low levels.
The Exterminator Quest
Small Sapphire, Small Ruby, Small Amethyst, Small Emerald
Troll Sabotage Quest
Elvenhair Rope or 200gp and Jerom's Family Necklace. You can sell the Elvenhair rope for money through the market.
The Ultimate Booze Quest
Light Shovel, 10 Platinum Coins.
Arito's Task Quest
50 Platinum Coins.
Nomads Land Quest
50 Platinum Coins, Jewel Case (Nomad), The Sacred Casket (Book), 2 Small Sapphires.
Pilgrimage of Ashes Quest
all blessings with 1000 gold discount (once only), 20 platinum coins. This quest is something to do before level 25, I'd recommend it if you want to invest in your future and also bless you for your death.
Steal From Thieves Quest
100 Brown Mushrooms, 100 Gold Coins. It doesn't hurt to take the item in this quest and sell it in the market.
Killing in the Name of... Quest
I like the Crocodiles task, the boss is named The Snapper. The Tarantulas task w/ invisibility (stealth ring) is a good idea for profit, the boss is named Hide. This quest will help you in the long run, it's good to be aware you might waste if your unlucky but consider this an investment in your future for experiencing and money if your lucky. If your looking for something that doesn't require killing creatures I'd suggest the other quests below. Also, here's a good tutorial on youtube regarding the tasks "Grizzly Adams Task Guide on Tibia for level 6-49: https://www.youtube.com/watch?v=LZ9Nqk_UOdg