For brush embroidery on cakes: 

Is it ok to use regular paint brushes and palette knifes that I can get at Michaels painting section, or it has to be special tools only for cake decorating?

There is a tread on here from 2008, people recommend using synthetic brushes.

Thank you.

AI would think any brush from michaels or any craft store would be fine just make sure its clean and doesn't shead....

Just dedicate the new knives and brushes to edible decorating and you're good to go....

Ok, Thank you all.

I got some great palette knives set at Home Depot with Martha Steward name on then (clearance!). STAINLESS STEEL! Wonderful AND THEY GO STRAIGHT IN THE DISHWASHER. $3 OR $4 FOR A COOL SET OF THREE. 

Maybe your Home Depot still has some (paint department) ?

 @Johnson6ofus, I will check  at Home Depot paint dept. Thanks

Crossing my fingers for you. My local store had 5 sets, and I bought two of them (about 7-10 days ago) Tried an on line search but the Home Depot site is lousy.

Good luck.