Can a Bulgarian passport holder get a VOA for Shenzhen for 5 days?

Hello, I'm about to travel at the end of May 2013 for a business meeting in Shenzhen. I'm flying to Hong Kong. Our partners from Shenzhen advise me to get a 5-days voa for Shenzhen. Is that correct, I mean can I get it at a border crossing and where? Your help will be highly appreciated!!!