There is fundamentally no way to audit record "views" in the platform, as you seem to be asking for.

If you want to monitor what has been "done" by someone in SFDC, there are a few things that it does automatically:

1. Who has logged in?

  - Setup > Manage Users > Login History

2. Who has changed this configuration/metadata?

  - Setup > Security Controls > View Setup Audit Trail

3. Who has changed this data?

  - Available for most objects as field history tracking, if it is enabled for 1 or more fields

But none of these audit that a user has searched for, viewed, looked at, reported on a given record.

I can imagine there are ways you could do this. One way could be to rebuild your view and search pages using visualforce. In the visualforce page action, you might call a method that stores which record/records were looked at, and by whom, in a custom object. If you weren't concerned with search results, but only if someone viewed the detail of a record, you could do this as an inline visualforce page that triggered a custom extension action in the action attribute of the page. If that would do, this wouldn't be so horrendous as rewriting the list/search page.

Another possibility might be using custom web service methods with your own custom UI calling Apex methods. Then, within each method ensure that when a record is requested/viewed, you store the fact that it was viewed and by whom.

But since there are no hooks for writing Apex that is triggered when data is viewed, there is no way to write a trigger for this, so you'll have to intercept the action to search/view somewhere between the UI and the object.

I'm only imagining here and have never built something like this, so maybe someone else has an actual example, or can imagine a more clever way than this...but I think this might be it.