I'd strongly suggesting setting up an account on
Mint.com.
Mint automatically tracks all your spending and sorts it by category.
Setup monthly budgets for each category and you'll quickly find ways to cut frivolous spending.
It does take some leg work initially, but it's well worth the effort to automatically see how much you spend on 'Restaurants', 'Fast Food', 'Entertainment', 'Clothing', etc each month.
Easily the best app/widget I use every single day.