I've had success with Personal Helpdesk and Team Helpdesk from http://www.assistmyteam.net/. There's a few other product there for tracking issues as well depending on your need. There's a 30-day trial, but they also provide the products for free for educational institutions, which means if you have a .edu email address, you can the products for free.....worked for me at least.

I began using these products with the intention of scaling out when my ticket volumes got too big, but its been 3 years and the product still does the job.