I started reducing my craft spending last year and I've have to say I bought 50% less than the previous year. My strategy:
I rarely shop big box stores and since the closest LSS is 25 minutes away, I don't make many quip trips just to browse
I rarely read emails promoting sales; I've unsubscribed from all but my favorite online stores
I no longer hoard those "special" items - I get more joy in using up something than buying new
Biggest change - don't buy something just because it's the latest need to have item. I wait a few months and in most circumstance the overwhelming desire fades away
When I felt the need to really, really, really have a new stamp, I bought a digi or made sure it was something I could use multiple times
The overall effect is that I'm enjoying having less because it challenges me to find interesting way to use what I have instead of hitting the store to find an easy solution.