In case it's of any interest, pretty much every primitive European bow found so far has been made from yew. Otzi's was yew (although slightly different to the norm as it was made backwards, without any sapwood and with the innermost rings of the tree used for the back) as were the Mary Rose bows, most of the Holmgaard bows, the recent Norwegian bows and of course the Meare Heath bow found in Somerset.
You read an awful lot of stuff both in books and online about English yew being lower in quality than yew from say Italy, and while that's true at the very top end, English yew makes stunning bows of all draw weights. It's easy enough to find if you're patient, and especially easy to find if you steer yourself away from the typical "English
longbow" design to start with.
If you're into primitive bows, and things like Otzi excite you then going for a Meare Heath / Holmgaard style design from yew will be fairly straightforward. Yew is incredibly forgiving (far more so than ash, elm or laburnum for instance) and can take quite a bit of punishment from inexperienced hands to still end up with a very good bow.
Going fully primitive and roughing out and shaping a bow using minimal tools, yew is excellent. You can strip the bark off, leave the sapwood intact and your back is finished. Scrape with a knife, scraper or spokeshave/drawknife at the belly until it bends the way you want and you're done. Keeping a bow wide and flat is the safest option to begin with and you should end up with minimal set/string follow provided you take care while tillering.
There was a discussion on Primitive Archer a while ago about how the "elders" would have tillered their bows, and the general consensus seemed to be that a simple tillering tree, or even just another pair of eyes would have been about the limit. When you see what the really experienced guys can do it makes a lot of sense. They can get a bow from log/branch to floor tillered using a few tools and a bit of elbow grease, and their skill and experience results in very little adjustment needed from floor tiller to final draw.
As Del said, jumping in is the best way to go. You can end up over-reading and over-thinking all this stuff and while second-hand information is good, nothing beats making a mistake yourself and learning from it.
I think the most common mistake most beginners make (I say this is a relative newbie to bow making and I'm still making the same mistakes!) is over-tillering. Trying to get everything perfect and even and smooth can easily end up preventing you from focusing on draw weight. Start somewhere sensible (35 - 45lbs perhaps) and aim to hit that draw weight. Get the tiller as close as possible of course, but you want to avoid having a beautifully tillered matchstick.
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