If there's a good way apart from doing it yourself I'd like to know it. DIY is time-consuming and I find it hard to motivate myself to submit sites to my own directory. But there is a feel-good-factor when you've found those good quality niche sites for those niche categories, and the knowledge you're directory is unique and contains relevant and useful links.
I think the basics will work just fine that is investment in promotion and marketing, then the URL's for reviews will come in, then you are off up & running but you must continue marketing 365/24/7, its not easy, but it does pay off