Where are you located? Shipping costs and fast are dependent on that. As for good, the common commercial sources, like Mouser, Newark, and DigiKey have equal quality. RadioShack is fast, but usually more expensive (excluding minimum order issues). Surplus houses (e.g., Electronic Goldmine) may be a little cheaper, but the bare boards might be a little oxidized and have scratches. 1/2 oz is fine for most purposes.
Read up a little more on the method you want to use and plan on ruining a few boards as you practice. For example, you would not use pre-sensitized boards with the laser toner transfer method. John