When I buy things now, I approach it differently. For example, today I went to walmart to get a few things. I got a clothesline (3.00) that will save me on electricity that runs the dryer, garden twine to help the sugar snap peas (that are 4.00 a bag at the grocery store) grow, and a nightlight so I can keep the lights off in the house but if my son wakes up he'll be able to see, but will be cheaper to power than a lamp.
I think its okay to spend your money if you look at the bigger picture- ask yourself "Do I really need this?" "Do I have something similar that I could use instead?" "Could I trade someone something to get this for free?" "What will it cost me to operate this over the long run?"
By asking these questions, you can make better decisions on spending, and save money, too. And in the case of things like the clothesline, CFLs, and my copper coffee filter, you are helping reduce your impact on the planet.