I pretty much obtain the following and aggregate them for my approach:
- Workshop manual (usually from owners club)
- Guide posted by someone from owners club
- Haynes Manual
The workshop manual is usually a pretty rigid example of how to do the job, doesn't offer much explanation of why you should do things a particular way and often assumes you have all the proprietary tools for the job.
Owners club guides usually offers a more practical insight as to why you need to do certain things and it's usually written in a more comprehendable "bedroom mechanic english". They also typically (and rightly or wrongly) advise how you can avoid using proprietary tools, and other shortcuts/insights. However, a lot of the time they miss out things, and are subject to any mistakes or assumptions the writer has made.
The Haynes manual is sort of a combination of the two, but can be vague in places.
An example of the above is the timing belt I recently did on the Evo, the workshop manual assumes you have all the tools, doesn't really detail the stripping down you need to do to get to the timing assembly, assumes you have all the necessary tools and a beam-type torque wrench (which seem to be like hens teeth in this country). It doesn't really explain things like why it suggests you should set the timing assembly to 1 tooth BTDC in places, and the actual reasons why you are doing specific things in the process.
The "go-to" owners club guide explains things more practically but negates to mention certain things like the fact you need to remove the power steering pump to replace an idler pulley, and i'm reasonably certain that the whole process of tensioning the belt is flawed.
In this case, as there is no Haynes for the Evo - essentially I had to research the whole thing and generate an aggregate approach that i'm happy with.
The above example is an extreme, particularly as the timing process on the 4G63T is a bit of a pig anyway, but it gives an insight into how I approach such a job.
Another recommendation is that you find another pal who is also interested or does his own mechanical work and learn from him/each other. Sanity checking and a second opinion is invaluable when doing these sorts of things.
Only exception I make is welding, sunburn is nasty from it 
