Hi Tawni,
Review sites can be really great. I almost started one, but now that I think about, I got sidetracked.

Anyway, I have a friend who has a couple that do really well. The first one is about vacuum cleaners (I can't think of the address) and the second one is
www.best-juicer-reviews.com He uses SBI to build his sites like I do, but he's more advanced than I am and uploads his own html.

But you can still have a look and get an idea of how a good review site is laid out.
Depending on the product you are reviewing, you can even have a slight variation to broaden your theme if desired. Notice how he has also included some popular healthy juice reviews?
Mark's advice is good, but if you are as new to this as I was getting started, you may just want to stay focused on your site instead of branching out on too many things at once. Unless, as Mark says, you will be refreshed and de-stressed by the outlet of a blog, too. Everyone is different, so you have to decide if it will help or hinder your progress.

Do you have a domain and hosting, etc., set up yet? Are you familiar with the whole sitebuilding process? If not, I highly recommend you consider SBI. They make the whole process very "simple" with all their integrated tools and step by step instructions, including researching a niche.
Let me know if I can help in any way. If you have been debating about a niche for a year, it is time to take the plunge and get started. Don't worry, the water's fine.