There must be a gazillion plans for Tesla coils through google. Please look them up:
http://www.google.com/search?hl=en&q=tesla+coil+basics
The basics of a Tesla coil is to have a few windings on one side of a transformer, and a lot of windings on the other. The voltage muliplier goes essentially linear to the ratio of the 2nd to the 1st. Of course, regardless of the multiplier, you can't get any more power of the output than you put in ... and using home current, that largely means about 2400 watts.
Ideally, the input core windings are only a couple, using the largest wire diameter to sustain 20amps of current. You should shop around for at least "00" rating wire. The secondary winding should be that very fine, shellac-insulated, transformer winding-wire that you always see in transformers for small motors.
This example:
http://ffden-2.phys.uaf.edu/211.fall2000.web.projects/r.pace/!tesla.html
... which if taken at the middle output value of 500kv, would require a winding ratio of about 4200 to 1, since 500K/120 is about 4200. That means that if the input winding coil is wrapped 4 times, you'd need 4x4200=16800 wrappings of the output coil.
Finally, ignore #2. Amperage kills in this application, NOT voltage. The 500kv output would be at 0.005amp, which is essentially harmless. Still, the tiny "bolts of lightning" are still not good for your nerves, so you should avoid having them strike your skin.