user testing

I have been working on a project recently where we have been performing user tests against Drupal prototypes. The audience is a mix of people from regular users of Drupal to marketers who have never seen the platform.

We are seeing a trend where people are regularly distracted and/or confused by things within Drupal core's interface. One example is we designed a test where users would edit a node and change the workflow state. Users found it challenging to even find where to go to edit the node.

I'm hoping to find a company in the Boulder/Denver area that can help us with website usability testing. Wondering if the group can send me some referrals.

Anyone have any good usability resources? Ideally, I'd like to take a course to brush up on my skills but any information would do!