I've recently started a website, although there are several domain names still available that could make it vulnerable to copycats.

I want to register these domain names as well. Should I just use a 301 re-direct to the main website or is there a better way for search engines?

301s are the best for redirecting as they're 'permanent'

Having said that though, since it's a new site with new domains, you won't get any search engine benefit from them. They're still good to have though to protect your name.