I might add to that, that mailing someone directly might not always get the response you wanted. Their mailboxes receive hundreds of mails a day, and your mail could easily get lost in those amounts.
For a fast response on Pre-Sales questions, i suggest you follow Colin's suggestion of posting in teh Pre-Sales forum at vbulletin.com, or mail to
sales@vbulletin.com. You can address the mail to Steve if he know about your situation, by putting his name in the topic.
And like Colin also suggested, you are here always welcome to ask (Pre-Sales) questions about modification, but also regular inquiries we will try to answr.