One thing I see that we can do to help draw advertisers to MRH is to add links to discussion threads on the forum.  It's simple to do.

For example, if you are creating a new thread about the Athearn SW1500 do the following. . .

I'm really looking forward to the latest release of the Athearn (http://www.athearn.com/) SW1500 in SP (http://www.athearn.com/Products/Default.aspx?ProdID=ATH96669)

When you come to read the forum thread, just click on the links and leave them open for a couple of minutes while you read the thread (and look at the manufacturers website of course).  Now, if the Director of Marketing of that particular manufacturer is "Johnny on the spot", he'll be monitoring the click through links and start to see that there are a increasing number of hits coming from the MRH website.  The more hits they see, the more they will be inclined to be an advertiser.

Hope this helps.