Depends on the company, when you contacted them (was it on the weekend?), etc. I've never had to wait more than 4 days. Note that if they're in a country that doesn't respect the DMCA, they're probably not going to respond at all. I've seen hosts showing up lately that advertise the fact that they ignore DMCA complaints. When you find yourself in that situation you really have no reason morally or legally not to DDOS the host or resorting to other questionable tactics.