It is true... while there is being thrifty, buying something so cheap that it hinders you is simply a waste of money. I say it all the time (I suppose the tiny quantarays are ok if you use nothing more than an F/4 aperture and nothing bigger than a baby or very small area)... in lighting and lenses, buy the best you can afford, even if it means going without for a longer time... your photography will thank you!
That said, last year I bought a Vivitar 285 just to test it out. Turns out it is now a permanent part of my travel kit. It may be an under $100 flash but when it comes to the strobist arena, this is one of the best values out there. This sucker packs as much power as a Nikon SB-800 but since it is not as feature rich, it has an incredible price.
If you want off camera TTL flash metering, one has to invest a LOT more and that means normally sticking to the same brand of company that your camera is. In the case of the Canon, you have no in-camera controller and that is where the ST-E2 comes in, but as mentioned (lol), its not a flash, it is an on camera controller.
TTL flash metering is ok under most circumstances, but becuase of the fact that you work harder with manual setups, you learn more and hence become better with an all manual setup. There is also a lot more control in an all manual setup.
The "strobist" way is to go all manual, so the extra costs of going this way is not really needed.
I would suggest that you go all manual, save a little money and at the same time learn how to nail your exposures. For wireless triggers for the budget people, I say you just cannot beat a set of modded Cactus V2s units. Do a search here for it, the mod is mentioned often.