Yea first rule is when buying any domain make sure the email address in the domain is the one the seller is using to email you with.
If they are not using it then always send an email to the email adress in the whois to confirm its really them who has access to that email and tell the seller to use that email address to contact you with.
If they give you some cock and bull story why they cant........
RUN!
If they are the admin then their email and contact info should be in the whois.
And if all else fails, then there is always Escrow.
