Alright, i just dont feel that the 3.0TD is the proper motor for your swap, find a 4bt cummins, or a VW 1.9tdi, or an isuzu 4 banger diesel, the toyota diesel really isnt that great a motor.
And on the bio diesel which is normally refered to a veggie oil and the DIY on it from what i have gathered is annoying and the machine to convert it is like a $3k upfront cost.
And to slingtoe, just a little comparision, my buddies VR6 jetta with a 6 speed manual pulls about 24mpg average, my TDI jetta with the 5 speed manual and a little tweeaked does about 45mpg on an overall year round calculations, that is a vehicle with its gas and diesel counterpart so the motor and tranny are the only difference, with me paying $4.00 a gallon for regular 40 cetane diesel, and him at $3.50 for regular as those are the local average prices around me, it costs me $0.09 per mile to run while it costs him $0.15 per mile driven, and those are fairly average numbers for each motor, now we can break this down in pickup trucks where the cummins is used vs the 5.7l Hemi, or in SUV's like the Defender where the TD5 is used vs the 3.9l Rover V8, but the same conclusion still comes out, the diesel even with the the price gap between the cost per gallon is still a large bit cheaper to run than a gasoline powered equivalent. Getting into LPG conversions is another story.