max-apprais.com was created on 12th September to an anonymous registrant, hosted on 22.214.171.124 at Katz Global Singapore. It's a copy of max-appraisal.com which is hosted on 126.96.36.199 at well-known black hat hosts YoHost.org.
top-name.net is a very familiar template hosted on 188.8.131.52 (Hostdime, Florida) also to an anonymous registrant (although it appears to be a Canadian resident behind all of this spam).
sedo.com are a well-known and wholly legitimate company and are nothing do to with the spam or scam.
The "pitch" email looks like this:
Originating IP for the spam is 184.108.40.206
From: "Domain Trade LLC"
Date: Wed, September 23, 2009 4:26 am
we are interested to purchase your domain [redacted] and offer between 50% and 65% of the appraised value.
We accept appraisals from companies such as
If you already have an appraisal please forward it to us.
Please let us know whether you are interested. Upon review of your valuation and in case of an agreement we send payments via PayPal for amounts less than $2,000 and via Escrow.com for amounts above $2,000, as well as further instructions on how to complete the transfer of the domain name.
We appreciate your business,
Domain Trade LLC
Of course, once they have taken your money for the appraisal, then you will never hear from them again.
If you have been conned by these scammers then start a PayPal dispute to get your money back. We understand that Sedo may offer a refund in any case as they are well aware of this scam. You might also want to file a complaint with the police, especially if you live in Canada where the perp appears to be based.