I know it's legal to sell my pictures to the papers and magazines, how much would they be worth?

Depends if you sell them through image stock houses or directly to the publications. The price will vary greatly depending on your 'name/reputation', image content, rights-managed vs royalty free, size, duration, where it's published, etc.

If you go the stock image route, you can sell them over and over and collect royalties which would be smaller than selling image rights one time based on distribution quantity, size of image in the publication, duration of the placement, etc. Try contacting Getty Images. It's a reputable company for selling your photography.

Overall, you can expect from $10-100 for royalty-free stock images. Maybe around $300 for Rights Managed sales.

Just to comment on a previous answer -you will not be able to sell them Royalty Free without releases from the band.

Your best bet IMO would be to see if a local newspaper wants them for a review of the show. Otherwise you'll have to find an agency/library that sells editorial (that rules out the microstock sites). Unless you have a huge portfolio of stunning shots you are very unlikely to get into Getty or Corbis unless you are prepared to pay to have your images included in Getty's "Photographers Choice".

I don't want to put you off but selling through agencies is pretty difficult. If they are as good as you say you might be better off trying to sell them directly yourself. Would the band like to buy some publicity shots?

I sell stock images for a living although not celebrity images.

worth exactly nothing...

magazines and newspapers tend to have their own people...