ZenPayroll Raises $20M From General Catalyst And Kleiner At $100M+ Valuation
techcrunch.com
techcrunch.com
Particularly for a small California business, there is no reasonable alternative I have seen, unless you feel like you have to go with one of the dinosaurs like ADP or Paychex.
I blog and Tweet about ZP somewhat frequently because it's been so refreshing: http://andrewljohnson.com/article/how-to-manage-a-micro-busi...
I'm sure you could also contact them for more information ...