Old 3D World magazine PDF scans have been taken down from Archive.org. They can still show up in search results there and at Google Search, from circa the 2008-2012 era, when it was taking notice of Poser in a real way (some tutorials from Brian Haberlin, some letters-page advice, freebies and an occasional review). But they are gone once you click through. So far as I can tell from search, the only way to get issues from that era now is to buy them in print from eBay when they come up. A pity, as it was quite fun to browse them occasionally and chuckle at what the oldware looked like. Or what a (now puny) PC £2,300 would buy you, back in the day. And sometimes they could yield up a useful nugget of obscure information.
I’d like to think that 3D World are preparing a $25 DVD with all their 2000-2015 back-issues as good digital scans on it, but such things do not tend to happen from big publishers. Being beholden to advertisers they view their complete set of back-issues as a liability that would distract attention from the current issue and its ads, rather than as an asset.
Though a couple of issues from even earlier in time are still online there, to give you a taste of what we once enjoyed each month circa 2006. Also most of the free cover-CDs as ISOs. I produced a survey of the 3D models on the latter, a few years ago. You may want to grab them now, just in case they go too.