Yeah the higher amounts (around $50K year) are SUPPOSED to be more technical support helpdesk. Lower amounts, in the $30K/year I would have thought would be more call center type job which does not require IT knowledge really. Now I know for a fact that people do get hired for IT helpdesk jobs, get paid the bigger salary, and wind up doing very little IT support and basically act like a call center and just route calls to other people/departments to fix the issue.
.02
PS: I'm not bitter, really....