GeneralWesc was a little off when he said that quarks 'form all elementary' particles.

First off, the quarks ARE (some of) the elementary particles, and they combine in various ways to form the the next level up, the hadrons, or quark-aggregates, made up of either a quark and an antiquark (mesons), or three of the same (baryons) -- quark-quark-quark or antiquark-antiquark-antiquark. Here are some examples of hadrons:
The positive pi-meson is an up quark and an antidown quark.
The proton is two ups and a down
(each for a total charge of +1, see Jesler's post.)

There are two other types of fundamental entities, the leptons and the bosons. The leptons include the electron, the muon, and the tau lepton -- the latter two being unstable more massive 'cousins' of the electron. Each of these three has an associated neutrino (these neutrinos are also considered leptons). All six of these have an associated antiparticle (just like with the quarks). On the other hand, there are the bosons. These are the particles which transmit the four forces of nature. They are: the photon (transmits the electromagnetic force), the W+, W-, and Z bosons (transmit the 'weak nuclear' force which is responsible for certain types of nuclear decay), the gluon (transmits the 'strong nuclear' force between quarks, and the force between the quark agreggates -- the 'hadrons' which include protons and neutrons, effectively holding atomic nuclei together), and finally the graviton, the proposed but as-of-yet-unobserved carrier of the gravitational force. Some physical theories include up to 12 other 'X bosons' which are not common in our cold boring universe because of their inherent high energy.

Once again, the leptons and the bosons are NOT quarks or made out of quarks, but they ARE fundamental elementary particles. Together, quarks, leptons, and bosons make up all the stuff in the Universe.