I forgot to welcome you here!
You know, I have similar fit issues as you do, although I am not petite ( 5'6") and have slightly bigger measurements (34-25-37). But what you describe about fit in the chest/waist/hip area is exactly the same thing with me. But I do not how being petite would affect that.
So here's some things I've figured out:
1) Wrap tops/dresses are THE best thing for women with our shape in my opinion. Look for true wraps, with ties that go through the hole on the side. They can be adjusted to fit perfectly, and accentuate our waist. I'm a huge fan!
2) Tailor is your new best friend - for taking in waists in shirts&pants ( you should buy them to fit you in the chest/hips) and to hem too long pant lengths/sleeves.
3) European brands to tend to cut things much smaller, so look into stores like Zara, H&M, Mango, Benetton, Esprit...
4) If you can afford it, contemporary designers also cut their things smaller ( or the vanity sizing hasn't kicked in yet). I look for them on sale: Theory, Nanette Lepore, DVF, BCBG etc.
If you have any more particular questions I'll be glad to help as much as I can!
