I was wondering where I might be able to find raw tracks that I could use to practise my mixing skills? I've searched on Google and the SOS forums and not yet got very far. Ideally, the type of music I'd like to practice on would be blues, rock, punk or metal.
Via SOS web site
SOS Reviews Editor Matt Houghton replies: Funnily enough, for the Mix Rescue article in this very issue (page 138), both the artist and Mike Senior have kindly agreed to let us make the entire Reaper project available for download. So not only will you be able to practice mixing on it (the full version of Reaper is free to download and evaluate for 30 days, and it's cross‑platform, which means that everyone can have a go, unless you're one of the few who are stubbornly sticking to Atari or Linux!), you'll also be able to take a look inside Mike's mix and hopefully learn a thing or two in the process.
As for other sources of raw multitrack recordings, I'm surprised you haven't had more luck with a Google search. Get the search terms right ("multitrack wavs” or "multitrack download”, for example) and quite a few sources seem to spring up, including some commercial artists, such as Nine Inch Nails, who have made material freely available (http://ninremixes.com/multitracks.php), and Peter Gabriel, who has held competitions where he's made material available for would‑be remixers. Good as Google is, trying a different search engine can also throw up some different results.
Finally, of course, there are always the potentially rewarding options of tracking some of your own material, working with someone else to track your own material, or getting out and seeing some gigs in the hope of finding a good local band and offering to record them for free! .