Time once again to start talking about upgrading my Mac. I need a much bigger HD, at least 2 gb, and I thought I might as well try to get a newer, faster processor at the same time, if I can keep the cost around $600. The only thing I use the Mac for now is web surfing, so I just need a machine that will process and draw web pages faster than my 6100. I know I can get refurbished 7x00 and 8x00 machines in my price range, so I just need some advice on which specific models to look for. And maybe some good dealers to get them from. Anyone got any thoughts?