90% of all my kid's clothes are 2nd hand... I spend a lot of time going to rummage sales and consignment shops for his clothes and I stock up the next sizes - anything that catches my eye... and I'm a bit of a brand snob (okay, huge brand snob).
This winter's, Lands End winter jacket and snow pants for Jake - I picked up at a rummage sale for $10... and that was 3 summers ago. Then the rest of the stuff I do buy new are on really, really good sale prices or at outlet stores for things that I just can't find like dress clothes for church.
Oh - and shoes... kiddo has a bit of a foot alignment issue, so I buy new and better quality so his foot doesn't get worse.