While some people consider the circular saw to be more of a carpentry tool than a fine woodworking tool, but some would disagree. There may be no more versatile basic handheld power tool than a circular saw. When used with a clamp-on straight-edge, the circular saw can be just about as accurate as a table saw and handle quite a few of the tasks that one would attempt with a table saw, particularly cutting sheet goods such as plywood or medium-density fiberboard. When woodworking on a budget, a quality circular saw should be the first handheld power tool purchased, as it is the one that will likely be the most useful as you get started.
Wooden mallets are mostly used for hitting your chisels when cutting joints (like dovetail joints or chopping mortises). You should never hit a chisel with a metal hammer. Build or buy a mallet that is made of fairly hard wood (e.g. maple, oak, beech wood, etc.), that will feel well balanced in your hand, and that gives you enough weight to chop with your chisels.