Trouble Connecting Printers and External Hard Drive to Airport Extreme

I have a MacBook Pro running Lion, an IPad and 2 laptops with Windows XP. I just purchased an Airport Extreme and would like to hook up an External Hard Drive and one or two printers/scanners. My Extreme is hooked up to my Verizon Fios Router via Ethernet. The wireless on my Verizon router is turned off and I can successfully connect to the internet. When I plug the USB of the external hard drive, try Canon MX850 printer/scanner or my Neat Desk scanner directly into any of my machines, I can use them. I bought a converter that allows you to plug 4 USB cables into one USB port on your machine and I can successfully use that with any of my computers to print or access the EHD. However, when unplug the EHD USB ink to my Airport Extreme or the printer cables into my AEX, I cannot connect to them. This happens whether I use the 4 port USB or directly hook one of the USB's to the AEX. It shows the Canon printer as offline. I am unfortunately also technologically challenged. Please help!! I travel for work and want to be able to access the AEX remotely to access my printer and EHD.