I'm looking for artists who paint in a style similar to that of Sam Francis?

Sam Francis ? Have you tried pre-schools?

I love painting like that!!!

i <heart> sam francis1

I had misplaced the colour versions of my Rorschach tests – thanks for finding them @filmfann.

Well, the most famous Abstract Expressionist was Jackson Pollock, who could probably also be considered the “original” Abstract Expressionist.
Willem de Kooning was another AE artist, but did more figural work.
Franz Kline’s work is a little more blocky than Francis or Pollock, and almost exclusively black and white, but of a similar style nonetheless.
Other abstract expressionists that come to mind are Friedel Dzubas, Helen Frankenthaler, and Jean-Paul Riopelle.

But really, you can find a lot of information on the Wikipedia page for Abstract Expressionism.

Was about to mention both Pollock and de Kooning, but @ParaParaYukiko beat me to it.

This list seems to be fairly comprehensive.