Power grill with homes propane tank

I just moved into a house that has a large propane tank outside. This tank used to fuel the hot water heater and the range in the kitchen. Now it's only for the hot water heater and we have an electric stove. So the gas connection from the range is now available. My plan is to connect a weber grill to where the range used to be so I don't have to run out and fill those small 20lb cylinders. The empty connection is in the basement so I'd like to use a flexible hose and a valve to control the gas. I'm just having a hard time finding the right fittings. Lowes didn't have the fittings I need to make everything work so my next bet was to try a local supply house. Does anyone have any recommendations for where I can look for the parts I need online? Or should I just had to a local supply and see what they can set me up with? I'll attach pictures of the line in the basement and the grill connection to show what I'm working with. http://i1018.photobucket.com/albums/af308/agn015/grill/1D6CEE35-298B-46C4-B0C1-ECD92CEEE14B.jpg http://i1018.photobucket.com/albums/af308/agn015/grill/0FCCF518-4F3A-4815-B491-4FFB5A0F9998.jpg http://i1018.photobucket.com/albums/af308/agn015/grill/C972B78D-7D0A-4FF8-B40E-28C584F21497.jpg