Methods for procuring a TZ number:1) Use your Meuchedet number.
2) Use your Bituach Leumi number.
3) If you have an Israeli CC, call up the company to see what number they have on file for your account.
4) Certain other companies may have a TZ on file for your account, such as HOT or others. Call them up to find it out.
5) Ask an Arab taxi driver for a receipt
6) Make one up. Make up any 9 digit number. You start off by multiplying x2 every other number starting from the second number. If there is a remainder, add it together ie; 7*2=14= 1+4=5. Now add up all 9 digits together. If the sum is divisible by 10, it is a valid TZ. If not, tweak it until it is divisible by ten. The number 087451464, we would start off by multiplying 8*2=16= 1+6=7. Then 4*2=8, it's still a single digit so it stays at 8. After finishing that process, we end up with the numbers 0+7+7+8+5+2+4+3+4=40. 40 is divisible by 10, so it means that the number is valid.
Handy site to check if Teudat Zehut is valid (and/or generate them)
here