Make sure of the following:
1. Thermostat is set on the "Heat" side if you have A/C
2. Thermostat is set high enough to call for heat.
3. Check for a tripped circuit breaker
4. Check for a breaker or other switch close by the furnace that be have been inadvertently turned off. There is supposed to be one in close proximity of the furnace.
5. Hit the "Reset" button on the furnace.
6. You said you just got fuel. Did you run completely out before that? If so you have air and possibly dirt in the line and it will need to bled out.
7. Have you changed the fuel filter lately?
8. Call all a furnace technician.