ZF - I got some $10 jeans and a few more tops/leggings for great prices at Kmart recently. They also had some cute cargos and some flowy dresses which looked reasonable. I try to put aside $10 a week to top up my wardrobe as I am still wearing stuff I bought just after DD1 was born - ridiculous as she is 5. I had to remember that I feel better when I look ok too - so whilst we have a budget I am trying to make an effort. Obviously the cheap stuff is not really good to last forever but I have done well out of it so far. I have also gotten some great cargos and tops from Ezibuy which has delivery and are quite reasonably priced. Try to make a list too so you have some idea of what to look out for. Fox in Flats has great tips and Frocks and Frou Frou has some great ideas for where to get pieces in larger sizes too. I also like looking at Birdsnest as they do outfits in terms of shapes - it gives you an idea of what to look out for too.
Don't underestimate how important it is to feel good!