As bigfatsirion said a drum smoker is cheaper and a great starting point to make sure it's for you.
If you're going to go offset then make sure you get thick steel. The cheap ones from bbq galore etc won't seal and the thin walls leak heat. The American ones are good generally. If you're going wood/charcoal then look at the Hark Texas Pro Offset for $1,500. It's thicker than me and smokes better than Angus Young.
