Re: How to build an engine??
Everything I have learned about working on engines has come from just getting my hands dirty and just doing it. The service manuals are invaluable to anyone working on an engine solely for the fact that it has your torque values. Other than that if you are anal and organized engine teardowns are pretty simple. Its when you arent organized that it becomes a night mare.
Since we live in the wonderful age of digital cameras, you also have the benefit of taking pictures of how things look before you take them apart so you can reference that later.
As far as a good bike to start with...well all these people talking about singles and such are kinda right, it wont do anything for you when you need to tear down an inline 4. I would suggest a late model 600, perhaps a 98 GSXR, something fuel injected so you get a feel for how to set up injectors and fuel rails, plus you have DOHC, which will get you used to timing and valve clearances. Its up to you how you want to start, but if yoou were like me as a kid and had to have the 2000 piece lego sets then you will get bored of the singles really fast. Plus with the late model 600 you could even track it, make it better, and you may even find newer understanding of your bike and the way it does what it does instead of taking it for granted.
Oh yeah....invest in ziploc baggies, they make life easy.