As mentioned already; most tasks can be done with common tools that you probably have already
if you work around your house, car(s), etc. I usually buy bike specific tools as I need them; instead
of getting a set - which will duplicate tools I already own(screwdrivers, allen wrenches, etc.). I like
Park Tools and Pedro's for bike specific stuff; bottom bracket tool, crank puller, etc. For common tools;
I like Sears/Craftsman for their no receip/tno questions asked lifetime replacement warranty.

SCREWDRIVERS by 1nterceptor, on Flickr