I just received an email from a customer who wanted some tips on painting the cast resin furniture I sell. I thought I'd share my answer:
You can use any of the acrylic craft paints, like Delta Ceramcoat, Folk  Art, etc; that's mostly what I use. No need to primer the pieces  before painting. 
 You are less likely to get brush marks if you
 - use really good quality brushes with fine bristles
 - use larger, square ended brushes for large areas
 - don't try to cover surfaces with one coat; several light coats is always  better.
 To get wood grain effects:
 - for dark woods: paint the whole piece a dark color first; then dry brush  with a lighter color.
 - for light woods: paint a light color first, then dry brush with a darker  color
 If you're going for realism, let the pieces dry overnight and then give  them a very light wash with brown watercolor (I use watercolor  pencils).