copyright and toy photographs. What I'd like to know is what about illustrations done from toys like Lego? What if it is an illustration done for personalised canvas prints or room décor? We don't think you need to worry if you're creating LEGO artwork and reproducing it as prints.
Who gets sued? LEGO Group appears to focus its legal efforts on copycat toy manufacturers, or those who trade off its name (such as those who use LEGO in a domain name). So, we doubt LEGO Group will pursue those who create LEGO artwork unless the artist is doing something that implies that LEGO endorses or is associated with the work.
Handy disclaimer. LEGO Group provides an intellectual property statement that includes a disclaimer you can use when posting Lego material at a website -- "LEGO® is a trademark of the LEGO Group of companies which does not sponsor, authorize or endorse this site." You can probably also adopt it for many other uses. Alas, as the company points out, using this disclaimer won't shield you if you're violating the law.
PS. Based on your spelling of "personalised," we're guessing that you're writing from the UK, in which case we have to bore you with our own disclaimer -- our advice is based on U.S. law.
UPDATE: January 2016. See this story for an updated take on how LEGO is handling LEGO-related artwork and bulk lego orders.