It is best to use a 0.05uF to 0.1uF capacitor near each IC,
although one capacitor for every two or three ICs may suffice. In
addition, a few larger tantalum capacitors (10uF, 20V is a good
value) scattered throughout the circuit for energy storage is a
good idea. Incidentally, bypass capacitors from power-supply
lines to ground are recommended in any circuit, digital or
linear. They help make the supply lines low-impedance voltage
sources at high frequencies, and they prevent signal coupling
between circuits via the power supply. Unbypassed power-supply
lines can cause peculiar circuit behavior, oscillations, and
headaches.