I think you are unlikely to blow yourself up with petrol. In fact with "black diesel" refined from waste motor oil, people often cut it with petrol to get it to viscosity.
How effective it is in the transesterification process is another question entirely.
http://journeytoforever.org/biodiesel.html is the recipe I'm familiar with, though I've never done it myself.
Where I live methanol can be purchased in any quantity you like (up to 44 gal drum size) from industrial suppliers. However for some reason it requires police clearance.
If you know anyone running a moonshine still they may be happy to give you their foreshots and heads which could be redistilled/compressed into something fairly effective.
Bulk Sodium Hydroxide available at farm supply stores. Potassium hydroxide available from soap-making suppliers.