Use the following trick to get easy experience and weapon proficiencies, as well 
as good weapons and money by selling loot from all the dead enemies. Once you 
reach "The Middle Of Nowhere" area, you will eventually get the "Circle Of 
Slaughter" quest. When do you do the quest, enter the arena, and kill all but 
one enemy (preferably a little one). Do not kill all enemies or the quest will 
end. Also, do not die or you will potentially lose a lot of money. After killing 
all but one enemy and collecting all items desired, exit out, and the game will 
save automatically. Reload your saved game, sell all desired items through one 
of the nearby machines, and repeat the quest as many times as desired. Note: 
There are three rounds; the last one is called" Final Round". Do not finish it 
if you want to repeat this trick.