I started by knowing nothing about bikes. This blissful ignorance did not deter me from building bikes (2 road, one tri, starting with the bare frame each time) using Sheldon Brown's website, rec.bicycles.tech, and Lennard Zinn's book. They run, mostly.

Zinn and Sheldon both write well and amusingly, so quite easy to read. Zinn now has one on tri bikes as well, with an entire chapter on how to travel with your bike.

rec.bicycles.tech is a bit superannuated, but searching its archives can find answers to the most recondite of bike questions. Of course you'll have to read critically as there's a lot of unhinged ranting as well; but anyone from slowtwitch.com is used to that ;-)