There's a reason artists prefer sable brushes!
And your local art supply store may be able to hook you up with smaller ones in sable, suitable for eyeliner, shadow-smudging, etc. If you want an angle brush, you can do it yourself, or take it to your hair stylist and ask her to do it for you. S/he is used to cutting hair on an even line!
What the art supply store won't have are big fat fluffy ones for powder, blush, or dusting shadow all over your lid.
If you can't afford to get good quality sable ones, your local Sally's beauty supply usually will have a selection of some very serviceable ones that will be much better than anything you can find in a drug or discount store!