I just bought some today for fixing my arc ls hybrid so that hopefully there will be no more flex problem. This is how I bought the silver conductive epoxy.
It is a $20 item so it won't pay to shop for it on the internet because of shipping charges. Just get your yellow pages and look under electronics. Look for large picture ads advertising components like resistors leds bulbs circuitry. Call them. Ask if they carry silver conductive epoxy. Ask them how much they charge. Make sure to call the ones closest to you first. Mine cost me $19.95.
For the regular epoxies and superglues and silicone seal for waterproofing my Arc's bezel, Home Depot had a nice selection of stuff in the caulking and epoxy aisle which were the same aisle in my store.