Best prices for acrylic sheets & tubes, needle valves

[Chin_Lee]

I'm not sure if this topic has come up before but I couldn't find much in the search except for one trend which was not very informative; I'm interested in knowing where all you DIYers purchase these products? I know of Industrial Plastics which is good for smaller size acrylic items but I've heard their prices are rather expensive in comparison. So for the sake of ALL DIYers, just wondering if anybody is willing to divulge their supplier of acrylic and needle valves?