http://store.solar-electric.com/ and they were very good to deal with for panels, controllers, etc. I also have the 75watt Siemens/Shell single crystal panels, but see that the new ones from BPSolar are multicrystalline. One of the advantages of the line is that the panels only weigh 17 lbs each, as opposed to 24 lbs for the Kyocera equivalent, and I have my 4 mounted so they are movable from side to side on lifeline rails to catch the sun. Bang for the buck in a reasonable size according to their site seems to be the Kyocera 130 watt if you have room for them; Kyocera is a major brand and seems to be very well thought of by the users.