I am not getting paid

In October of this year I was hired as an independent contractor. My pay was supposed to be Net 15 from the date of my invoice. To date, I have not been paid all that is owed to me and they are now late by 2 months. On top of that, they brought me on as a full-time salaried employee at the beginnig of December. My first check is ue to me on January 1st, 2006. If I don't get paid, am I able to claim Constructive Termination? Also, there is a non-compete clause in the contract. Would his breach of contract nullify that as well? What other options do I have? There are also other "Independent Contractors" for the company in the same position as I am, that have not gotten paid either. Can we file a class-action suit against the company? What other options do we have in that regard? Thanks, in advance, for your help.