Some good advice, but there's one glaring common thing that many people are saying which is the WORST advice at all.
DO NOT, and I repeat, DO NOT, cancel ANY cards! Cancelling cards hurts your credit score!!
I hate hearing the "cancel your cards", as many people giving out this credit advice are uninformed about how your credit score works.
Not only will cancelling your cards lower your score, but it may prevent you from getting a card when you need it later on down the road for legitimate charges or even getting a mortgage or a reasonable car loan. While credit score calculations are in the form of algorithms that cant be breaken down to an exact number, they all share several traits - one of which is your score is automatically lowered if you dont have a major credit card open (such as a MC, Visa, or AmEx), in addition, closing major credit cards stops the growth of the average age of your accounts, thereby hindering any growth or stability.
Also DO NOT, and I repeat DO NOT, ask to lower your credit line. This, too, lowers your credit score. Your credit line should be roughly four times what you normally charge in one month (i.e., if you have legitimate charges of $1000 monthly, the minimum credit line you should have is $4000). If you opt for a credit line of 2K, for example, the credit agencies will see you utilizing 50% of your "revolving credit" available to you, and find you to be a high risk.
If you really have a control problem with spending on your card - simply cut them up. You cant use them if they're damaged. The account will still be valid, you just wont be able to make any purchases until you recieve a functional card in the mail.
If simply cutting your cards isnt going to work, do not take the advice of anybody on this board (sorry guys!), but instead, go see a credit specialist who can give far better advice to help you out! Your credit score is just as important, if not more, than simply your current balance on your credit card, and it needs to be treated as such.