Hi there Jack,
I would like to ask you an important question, but i'll save that for later.
Just to note, you can use a PIC microcontroller and crystal for super accuracy or use the internal RC oscillator (for about 1% accuracy) and program in some simple code to generate a very simple 1Hz oscillator. If you dont have a PIC programmer, get one (just kidding) or ask someone to program a chip for you for the cost of the chip (about $2 USD). If you use the internal RC oscillator, you dont even need a crystal or external oscillator. The program to do this is SUPER simple and very short too. If the code is adjusted for the particular RC oscillator on chip, the accuracy can be very very good and be stable at room temperature too with only a tiny variation for plus and minus say 10 degrees C.
Not everyone likes or wants to use microcontrollers and i understand this, so another solution is to use an LM339 and a capacitor and a few resistors to make a 1Hz oscillator. It's a very simple circuit and is not too sensitive to voltage variations, and accuracy can be adjusted to very very close to perfect if you have a frequency counter available. It depends on how much accuracy you really need.
Another solution is a 32.768kHz crystal oscillator, CD4020 chip, and 74LS161, that makes up an oscillator/divider to get 1Hz out but yes it takes three dip packages. I've actually used this solution though and it isnt too hard to build, and a high accuracy oscillator can be found if needed.
Recap:
1. LM339 oscillator is the simplest and cheapest (1 cap, four resistors and maybe a potentiometer for perfect adjustment)
2. uC, like the PIC type, very simple but you need a programmer or someone to program one for you.
3. 32.768kHz osc + CD4020 + 74LS161 (or similar), not too hard to build and fairly cheap.
4. CD4521 + osc (Hero's solution), very simple if you can find a C4521 that works up to 4.2MHz at 5v.
Ok, now for the important question:
Are you really after a 1Hz oscillator, or a 0.5Hz (one-half Hertz) oscillator?
The reason i ask is because many times a person is looking for a one half Hertz oscillator but they ask for a 1Hz oscillator. The difference is, if the oscillator is going to be used as a 1Hz time base for say a frequency counter, the frequency really needs to be one half Hertz, not 1Hz, because the period of time the 1Hz wave is high is only one have second and they really want 1 full second. The solution there is to use a 50 percent duty cycle one-half Hertz oscillator.
Of course this may not apply to your application, but i thought i would ask just in case. No problem if you dont really need this.