I haven't read the full thread above in detail, but here's what I do. I'm lucky in that I have access to AutoCAD. I usually dig online to find a photo that's as close as possible to a straight-on side or top view. Then I insert into CAD and scale the photo up/down until it matches a known (or reasonably guessed) dimension. Then I draw it out by "tracing" over the inserted image. I turn off the image to print it out to-scale.
I don't want to come off as snarky, but I do want to say a quick word about the term "blueprint". I understand that it is part of the American vernacular to mean "construction plans", but it's actually something different. It's the technical name for an ammonia and light/heat based drawing reproduction process that hasn't been widely used in close to 20 years (if not longer). Back before large-scale xerox type copiers were cheap and common, this was how all drawings were reproduced in the construction industry. It was a slow and smelly process (ask me how I know).
The reason I bring this up is because if you go into a print shop today and ask for blueprints, they are either going to a) give you a dumb look, b) just laugh outright, or c) politely inform you they no longer have blueprint machines.
Call them whatever you want when you refer to them amongst yourselves, but be careful what you ask for if you need to get something printed.
ETA: Ok ... I just looked back and realized how old the first post in this thread is - 2002. Ooops. The last time I worked anywhere with a functioning blueline machine was 2003 - and it was already considered kind of a relic by then. My comment is still valid for today, but maybe not so much back when the thread started.