Al from Black Gate has an interesting post on marketing the OSR. The main reason for the marketing issue is the result of our diversity. None of companies specifically making OSR products individually have the budget for marketing of even a 2nd or 3rd tier publisher. Collectively we sell a lot but each only spend our little slice.
Given time, a handful of OSR commerical publishers will grow large enough that they would be effectively a 2nd or 3rd tier publisher accompanied with a bigger budget for marketing.
However if folks want to jump start the process then it seems to me that a manufacturer's associations focused solely on pool advertising dollars. It would have a membership fee of between $50 to $100. Large enough that only folks serious about commercially publishing will pay it but low enough that it isn't a barrier to entry. In short signing up means you are committing yourself to be a professional.
Again it's focus needs to be limited or politics will be a big problem. It will be little problem as it is. Plus there are groups like TARGA, GaryCon, etc that focus on convention, and other aspects of the OSR. This doesn't need to duplicate what they do.
To summary what I am suggesting If ten publishers sign and the fee is $100 then it will have a $1,000 budget. The members appoint a marketing team and they design the ads, buy X amount of adspace on the web and print. Part the budget will have to be used to pay artist and layout folks leaving the rest for the actual ad buys.
This summary leaves out a lot of details that would have to be hammered out like the ad content, who gets to approve stuff and so forth and so on. One thing I do suggest that a omnibus website be maintained by this manufacturing group. That space on the site be reserved for ANYBODY involved in the OSR. Just submit a link and it will made part of the directory. The content of the actual paid ads will be reserved for dues paying members.
Also if an existing group, like TARGA, want to expand themselves to do this that would work just as well as long as the publisher have collective control over how their dues are spent.
The philosophy of doing this is that making people aware of what we do keeps our hobby healthy by having new gamers come and start playing the games we love. It helps both the commercial and non-commercial side of the hobby.
Unfortunately I don't have the time to take on a project of this magnitude. But I hopes this inspires folks to think about this issue and certainly if it comes into existance Bat in the Attic Games will be joining.