This is old, so maybe you have moved on but...
About a month after your post, we released the SODA.NET library, which is also available as a Nuget Package. This is an SDK written on top of SODA, with some helper methods and classes.
The example code is written in C#, but from within VB.NET you should be able to do the same types of things
'client provides access to a given host (data.cms.gov)
Dim client as New SodaClient("data.cms.gov", "YOUR_APP_TOKEN")
'a resource reference provides access to that resource's data (using the 4x4)
'we are modeling each record in the resource as a Dictionary(Of String, Object)
Dim resource = client.GetResource(Of Dictionary(Of String, Object))("qcn7-gc3g")
'a SoqlQuery defines how you want to query a given resource
Dim queryForNPI as New SoqlQuery().Where("npi = 1801093968")
'execute a query and get the results back as a Dictionary(Of String, Object)
Dim results = resource.Query(Of Dictionary(Of String, Object))(queryForNPI)