This is something I quickly put together when I was working for a client who had hundreds of spam registrations.
Install as usual and go to
ACP-->Users-->Mass Delete Spam Users
That will show all user accounts where a user has less than or equal to X (configurable via ACP options) number of posts but has urls in homepage or signature or about fields.
That page will show you the user, content in his homepage, signature and about fields and his message count. You can either delete individually or multi-select and delete.
You can also set an option of how many users you want per page on that page so that you can delete quicker if you have hundreds of spam accounts.
Options are in ACP-->Spam Management (first two options).
Be very careful though as it does not ask for confirmation and will straight away delete users selected. This add-On is unsupported and comes with no strings attached. Use at your own risk. Ideally this should only be used to delete spam accounts with 0 posts.