My advice is this--if you absolutely need the flash on camera at some point or another, get a Canon flash to start out with. My first flash was a 580EX, and there have been times I was certainly glad I had it (as the situation required the less-flattering flash-on-camera approach). However, I can tell you that 95% of the time my 580EX sits in my gear bag unused. Another 3% of the time I'll use it off-camera (when I need more umph out of a flash), and the other 2% it's used on-camera. I don't use it often simply because of the high replacement cost of the flash. I'd much rather beat the heck out of my cheaper, used Vivitar 285HV flashes (most bought for less than $50) than to risk damaging my 580EX. As it stand right now, I've got 3 Vivitar 285HVs, 1 Vivitar 285, 1 Vivitar DF400MZ, and 1 580EX.


Having non-TTL strobes means I have to adjust the flash power manually. However, after a little while, this becomes second nature and isn't a problem. If I were shooting weddings frequently, I'd probably want (and could thus afford) having several Canon ETTL capable strobes. However, I'm doing just fine with my Vivitars. I love them. They are quite rugged and reliable (although some of the newer 285HVs have had quality control issues).


I'd suggest getting a relatively cheap basic setup first--cheap flash (used or new Vivitar 285HV, used SB-24/SB-28, etc), white Westcott collapsible umbrella, LumoPro LP606 lightstand, LumoPro LP633 umbrella swivel (the umbrella LumoPro items are available at MPEX), and some way to trigger your strobe (either cheap ebay trigger or Cybersyncs--you might need a hotshoe adapter to connect the receiver unit to your flash depending on the system you choose).