One a hub is posted how long before you can post it on a personal site?

As long as you hold the rights to the content, you can do whatever you like with it. However, if you want to avoid a duplicate penalty, you should avoid reposting hubs on other sites, or copying content from other sites(including your own) to use as hubs. It's also worth noting that content that appears on other sites will not be allowed to have any outbound links on the page, here at HubPages.

Instantly. Use those weird sharing thing icons at bottom of Hub page once it is published. I do! Peace.