SharePoint may not be the best platform to create a Service Desk type system on it as there are free systems out there you can use without much set up (i.e. Spiceworks).
However anything can be set up in SharePoint, you just have to put the effort in to make it work.
My business requirement was to replace the dated ASP.net Help Desk system in SharePoint Foundation as this is a common platform they use for other systems and registers. SharePoint is due to be replaced with SharePoint Standard for Document Management, however this was required before then.

Here’s what I came up with:
(Note: everything is set up OOTB with no addins or costs.)

End Users View:

Service Desk Home Page

Requests in Progress

View of Request

Clicking ‘Add a comment’ from ribbon

Comments Tab

Closing a Request

Admin View:

(Not all views are shown)

Notice extra Menu Items

Requests Assigned to Me

Extra functions in Ribbon

Admin Page, Graphs created using SSRS

Creating a New Request

Adding a new Incident, for IT purposes only

If Incident is current, will show up in multiple places

Wiki Help Center:

What Makes this Work

The system is set up using a number of SharePoint Lists and 1 SharePoint 2010 Workflow.
Some of the views are using JavaScript and CSS to display data differently.
I will create a more detailed post on how to replicate the system in due time, but the basics are the following:

Main SharePoint Lists:

– Email Options: Workflow references this to know who to email to. This way the admin can make changes without needing to use SharePoint Designer.
– IS Service Desk: Main Request list. Multiple forms are created in SharePoint Designer to hide fields not relevant. List has about 24 columns
– Site Pages: All the the different end user views
– IS Admin Pages: All the different admin views, permissions locked down
– Site Assets: JavaScript, CSS, Icons Etc.
– Attachments: Self Explanatory

One SharePoint 2010 Workflow created with SharePoint Designer

Basic stages are:
– Initialize Request
> Set due date
> Set Requester
> Set CaseID
– Update Comments
– Assign To
– Re-activate Request
– Quick Close
– Resolved

SharePoint Request Form:

Tabs – http://onlinehtmltools.com/tab-generator/#skin4-top-basic_display
Columns – http://gridinator.com/
Custom Layout – http://www.markrackley.net/2013/08/29/easy-custom-layouts-for-default-sharepoint-forms/

Multiple display and edit forms created in SP Designer to hide feilds for views on Service desk list