Beacon Sign Co

I was contacted back in October, 2009 by Fairmont Sign Co to install some plastic letters on a building at a local business and I gave them a fairly reduced rate thinking that I could pick up a new customer. Well I got the customer but I wish that I had not. They continously called wanting to know if I had got the work done and I kept explaining to them that I could not install the letters until they had them shipped to me. Finally in January, 2010 I finally got the letters and put their job ahead of some others and got the job done. I took before and after picture sent copies of my insurance and everything else that they wanted and sent it all in. I emailed them a copy and also sent them a copy in the mail and followed up later to be sure that they had everything to get me set up as a vender and pay me paid and was told everything was in order. Now it is the last of April,2010 and I still have not been paid and can not get any one at their office to even take a phone call from me or return a call. I guess this is how they got to be a large company , by not paying their bills and using the money for other things. Has anyone else had any simuliar problems with them?