Here is a solution I've been working with: http://jrkerr.com/boards.html. I've only used it for stepper and PMDC motors so far and I've not yet mastered its communication protocol so I have to use the auxillary Motion Basic chip to control it with an Arduino . Note that if you are able to build your own board there are a number of example circuits provided in the thorough documentation so you can buy the chip only and save a lot. The board uses an LM18200 h-bridge but it will work with any number of less expensive chips (L298, L293, etc. ). Jeffrey Kerr also provides very good email support. There is also a complete library for use with PIC microcontrollers which I'm sure could be ported to Arduino if you are a skilled programmer, something I'm still working on :).