Howdy Brant,
You can update the website url by logging into your Google account, then clicking "account settings" at the top right. After that, click "Google Places", then update the listing(s) of your choice.
Citations aren't necessarily links to your site. SEOs more use the word to represent 'mentions' of your website, along with address, phone, etc throughout the web.
Here's a recent video I highly recommend you watch.... The Basics of Local SEO.
Also, David Mihm posted an updated version of the Local Search Ranking Factors, which I highly recommend you read. All of it 
Don't forget to read every word in the Google Places Help Center as well.
I know it's a lot to study, but you're engaging in the optimization process, so it's crucial for you to understand as much as possible.
If you're still having trouble after all of that, I'd be happy to help you with some specific advice, just let me know (free of course). Otherwise, I'm sure some other mozzers will post some great ideas to this question as well 
Does this help Brant?