The first and most important piece of equipment to purchase is a digital multimeter. Buy a digital multimeter such as Jamco 2131127 or Radio Shack Model 22-182. Buy a set of 10 alligator clip test leads such as Jamco #10444. Buy at least one prototyping board such as Jamco #20723. Prototyping boards have an array of sockets that allow electical components and wires to be quickly and easily connected without solder. Always purchase IC's (Integrated Circuits) as DIP (Dual Inline Package) style (not surface mount) so that they can be plugged into the prototyping board. Buy a spool of 22AWG solid, insulated wire (Jameco 36881) for connections on the prototyping board. Buy a spool of 22AWG stranded, insulated wire (Jameco 126077) for connections elsewhere. Buy wire strippers such as Jamco #215889. Buy a power supply such as Jameco #190960 ($29.95). This supply provides +5 Volts for digital circuitry and +/-12 Volts for analog circuitry. You will also need a Jamco #38050 power cord and #15844 din 5-pin mating connector for this power supply. You can use batteries instead as described in the "Battery Power" link below. Buy a soldering iron such as Jameco #195223 for making permanent connections.