-a soldering iron,not soldering guns, are an essential to any devoted electronics hobbyist. You should spend no more than $8-10 on a good iron at the electronics goldmine: http://www.goldmine-elec-products.com/prodinfo.asp?number=G6552 . And, if you use your iron a lot, like 5 or 6 projects a day, then first off, don't you have a job?, and second off, you will want replacement soldering tips. Also really cheap at the goldmine: http://www.goldmine-elec-products.com/prodinfo.asp?number=G15644 . and, of course, you will need solder: http://www.goldmine-elec-products.com/prodinfo.asp?number=G16713 .
-sidecutters, also known as dikes, are great for cutting leads. they give a much closer cut than scissors, to help prevent shorts.
2: parts and things
-capacitors are little towers of power. they store electricity in one spot, and one of my favorite things to do with them is to put one in parallel with an LED to make it fade when the circuit is turned off. what fun...
-resisors reduce current. so useful all over the place. you gotta use one with an LED when you hook it up to just about anything except for a coin cell. such cool things!!!!1!!!
-switches are an essential. I don't need to explain it. good ones to get are spst, spdt, dpdt, and pushbutton.
-computer wire makes great jumper wire once it is tinned or twisted into a point.
-battery holders are the power supply to your projects. get the cheapest holders you can find- quality really doesn't change based on price.
-protoboard, also known as perfboard, is what you mount all that stuff on
-integrated circuits, spefically digital to analog converters as well as the 555 timer are essential, as well as IC sockets for them, so that you can easily replace them in case one malfunctions.
-motors are, like LEDs, pretty self-explanitory, just not as essential.
-potentiometers are variable resistors, used in loads of audio projects, like the pwm for guitar .
-voltage regulators are an essential. the 2 most used are the 7805 and 7812 .
-you may also want to have a few USB ports , dip swithes , 7-segment displays , reed switches , and relays .