If you find street photography scary, try approaching a busker this way: hold out some money in your open hand as you approach them. Say "I like your music." Drop the cash into their hat/case/whatever, then add "Is it OK to take a picture?".
After you've done this a few times, you'll find you'll be adding to your gallery in no time at all. It's a fair exchange for both musician and photographer. I always leave an email address if they ask for a copy of the snapshot.