I'm developing a Silverlight web part and can't use server-side objects like SPList. I normally get items from a list called "Locations" which has two fields - "Title" and "WOEID". The problem is I'd like my webpart to create that list in case it doesn't exist before getting data from it. How should I do that?
You can use the classes of the Microsoft.SharePoint.Client namespace.
Here is an example how to retrieve the lists of a site.
And here is an example how to add a new list.