Hi mcelec
Having briefly looked at both sites, I see no visual similarity, even though you both seem to be working in a similar area of charity related activities.
There is no record of their having registered the words Legacyevents or Legacy Events as trade marks on the IPO website, and although they make some robust statements in their terms and conditions about their intellectual property rights, this seems to relate solely to copyright in their website and the forms etc which can be downloded from there.
Although there is some similarity between the two URLs I think this is inevitable given the area that you are both working in. The words 'legacy' and 'legend' are entirely separate in meaning and in my opinion unlikely to be easily confused. Therefore I am at a loss to see what grounds the other site might have for a claim of stealing their intellectual property, and indeed what IP they feel has been infringed. Unless you have copied swathes of text from their site or their entry forms (which does not appear to be what they are complaining about) then it is doubtful if there are any copyright issues here. URLs are functional things just like postal addresses and therefore would not normally attract copyright. In any case I would say there are no grounds for saying that 'legendevents' is a copy of 'legacyevents' by any measure normally adopted in such cases.
There are two areas in which a claim might be made. The first concerns Domain Name disputes, for which there is a recognised resolution system, details of which can found here:
http://www.icann.org/en/udrp/udrp.htm with an explanatory article here on Wikipedia
http://en.wikipedia.org/wiki/Uniform_Do ... ion_Policy
The second area is called passing-off and is dealt with under common law. It is not technically an IP issue, although very closely related to it. Since there is no actual statute defining an offence of passing off, it is not an easy matter to bring a claim. Essentially the claimant needs to prove 3 elements:
1. That goodwill attaches to his goods or services,
2. That the defendant misleads the users of those services as to the origin of the services he (the defendant) provides, and
3. So causes damage to the claimant's business.
It is not necessary for any misrepresentation to be deliberate or the result of bad faith, ie that the defendant deliberately sets out to deceive the public. However, bad faith may be an aggravating factor.
Interestingly there has been a case involving URLs:
Phones 4u Ltd v phone4u.co.uk Internet Ltd [2006] EWCA Civ 244. In that instance the claimant (Phones 4u) won on appeal. If you have time, I recommend reading the judgement in full as it serves as a good summary of the factors involved in passing off.