Gamer, I can comment on how long a cMoy took from a beginner's perspective.
It does help to do a fair bit of background reading, but essentially you can have a read of Tangent's cMoy site, and order the parts in the parts list. There may be a couple of decisions you need to make while you are ordering, but you can get the parts in! I put most of the amp together (bar casework) in one evening.
At that point, I could solder, but not neatly
I was a newbie with DIY electronics. I think putting the amp together (up to the point where I could connect things to it to make a sound) took about 5 hours.
I had immense fun doing it
Very worthwhile if you are up for some effort.
If not - buy one ready made and skip the construction and possible fault finding stage. The assembling parts stage can also be rather frustrating if you can't find a specific part, but with the cMoy that is unlikely.
If you are interested in building, I definately reccomend that you start with a cMoy - purely for the experience. Tangent's write up on the cMoy is very friendly to those with no experience. The write-ups for the more advanced amplifiers assume you have some prior knowledge and experience.