R – TagLib# Windows distribution? Or another good ID3 reader

To get started with extracting ID3 tags in Python, there's a module for that.

from ID3 import ID3

mp3_filepath = r'/music/song.mp3'
id3_data = ID3(mp3_filepath)
print 'Artist:', id3_data['ARTIST']
print 'Title:', id3_data['TITLE']

More info on ID3 module.

If you want to recursively search a directory for mp3 files, the built-in os module can do that:

import os

def mp3_files(root):
  # this is a generator that will return mp3 file paths within given dir
  for f in os.listdir(root):
      fullpath = os.path.join(root,f)
      if os.path.isdir(fullpath) and not os.path.islink(fullpath):
          for x in mp3_files(fullpath):  # recurse into subdir
              yield x
      else:
          if fullpath[len(fullpath)-3:] == 'mp3':
            yield fullpath

for p in mp3_files(root_dir):
  id3_data = ID3(p)
  print 'Artist:', id3_data['ARTIST']
  print 'Title:', id3_data['TITLE']

Reference.

In terms of creating the database, you don't need to reinvent the wheel (storing music data is a common database problem) -- a Google search will help you out. Here's one example.