Only familiar with the Toronto area currently, Motion Recruitment and Randstad Canada. In my experience no recruiters really understand or deal with LMIAs or LMIA-exempt work permits (like the Canadian version of the TN visa), so expect an uphill battle if you don't already have PR or at least an open work permit.
I've worked with only one company that specializes in helping with LMIAs, and they only do tech (so not just ICT but specifically programming engineering roles).
