Editing these tags manually can be a laborious task, but fear not, the contributers at MusicBrainz offer a solution to your problem. As they say themselves:
MusicBrainz is a community music metadatabase that attempts to create a comprehensive music information site. You can use the MusicBrainz data either by browsing this web site, or you can access the data from a client program — for example, a CD player program can use MusicBrainz to identify CDs and provide information about the CD, about the artist or about related information. You can also use the MusicBrainz Tagger to automatically identify and clean up the metadata tags in your digital music collections.
The website has a number of applications that you can download which access the database. The one I found most useful was Picard, which provides an interface to search the database and use the information to rename and tag the audio files with the correct information. I didn't find Picard particularly intuitive to use; however, the authors have provided some quality documentation to instruct users on how the application works. Here are a few images of the software in action. If anyone struggles with the software after reading the instructions, leave a comment on this post and I will record and post a video of how to use it.
Using the search facility on Picard opens up a listing of matching information on the MusicBrainz website. I navigated to the appropriate album listing, and pressed the green 'Tagger' button.
Picard presented the information in the right pane. I selected the files in the left pane, pressed the 'Scan' button, and when the list in the left pane was empty I pressed 'Save' to make the changes.
I finally decided that I needed to create and correct the tag information on my audio files after becoming sick and tired of some of them not registering with Audioscrobbler, which is the software used on the music based social-networking site LastFM. The software records all the music you play on your computer, and even some portable audio players, and creates charts from the information. You can see my page here. The site enables you to create fancy widgets to put on your blogs, social networking pages and other websites too, like this one:
So get those audio files tagged and let the World that you are obsessed with prog rock.