Tabletop Spinning 
Direction Control
Practice controlling the motion of the coin after you set it spinning. If you use your right hand and spin the coin anticlockwise the tendancy of the coin is to spin in a leftwards arc. With practice you can control the diamater and duration of this arc.

You can also make the coin spin without any lateral motion. If you combine this with the Two Finger Start method you can get the coin spinning on very small surfaces which looks really cool. An extreme example of this, and an excellent trick is to balance a US half dollar, heads up on the tips of the thumb, index and middle fingers of one hand. Now take a one cent piece and make it spin on the surface of the half dollar! The trick is to prevent the one cent piece from spinning of the edge of the half dollar by adjusting the angle of the half dollar. This is really hard but very impressive, even if you only keep the one cent piece spinning for a few seconds.

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Continuous Spin

Once you have a coin spinning you can keep it spinning indefinately by gently flicking the edge of the spinning coin to impart extra spin on it. Try and keep the coin in one place while continually imparting extra spin. Typically the coin does not stay exactly in place but keeps moving in a small circle.

Spin Stall
Start by getting a coin spinning rapidly on the table. Now sharply press down on the top of the spinning coin with an index finger so that the coin stops spinning and is held edgewise between the table and the index finger. Flick the coin with the middle finger to start it spinning again.