i finally have enough money to be able to commit to b-sides (because I quit drinking!) I'm not sure how it works though. Will I have to log in on my desktop to get access to the feed? Poking around here, it seems like there's an email which should go out eventually.
Yes, when you sign up, you should get a registration email.
You use whatever tool you normally use to get the podcast (iTunes, direct download, etc.). The only difference is that the tool will ask you for a username and password.