Hi Johnny
Now, I'm no expert at this (you need
Andrew) but this is what I've picked up from dealing with butchers for our pigs. Beware some of this might be tripe!
For streaky bacon you use the belly, which could otherwise be used for belly strips or sausages. For back bacon it's loin, which is a prime chop cut I think.
A whole ham is normally (I think) the upper part of a hind leg, and will be huge (at least 10lb I'd think). We've never tried it ourselves, but I think the main issue is preventing spoilage if you keep it bone-in. If you have a tame butcher who will tunnel bone it for you then that may be a better bet.
Beyond that we just say what size of joint we want - 2-3lb for us, but if you've got a big family you might want larger joints. Don't forget the heads, shanks, trotters, skin and offal too, if you have a use for them.
We've always negotiated cost with the butcher - it never seems to make much odds what we want done.
Hope this helps, if you learn more please share!
Dan