My thoughts are:
One thing that is missing when you actually think about it is a coherent and cost effective advertising strategy for bands.
Using Google Adwords for music is not cost effective unless you are selling items valued over 10.00 dollars. Better still 20-30 dollars.
One thing that might work would be a way for bands to be marketed online properly.
Google works well for genre listings, cover versions or FREE music.
I think initially you need to find great bands, quality bands and link them by category or genre. This is not being done. The closest you get is Myspace but the categories are not reviewed at all. I've seen major label artists listed as unsigned and also unsigned listed as major etc
ukbands also lists bands.
The amount of work required for this is huge. Do you have the time for this ? I would suggest you concentrate on your own music, your own strategy, make some success out of it and then sell an ebook on Clickbank to educate others on how you achieved your success.
Other than that another strategy with online advertising is to build up your site visits where you can give away FREE downloads but you must think long term here and aim to get up to a million visits a month. You can then auction advertising on the site to musicians using Adbrite and/or Google.