A formal letter

Dear Sirs, 

I contact you am writing to request information regarding (about) the various musical events taking place next month in New York City.
Currently, I am working in a (I work for) a Music Magazine and I would like to write an article about them, forthcoming events. (you need to say its about the events because "them" might refer to the magazine) I am shure sure it would be a great experience for me  (interesting and informative for me) and readers of my magazine. (a great experience is much too general - what exactly are you experiencing?)
I would appreciate detailed information concerning places and dates of these events. (I should be grateful if you could send me details of the events together with information about venues and dates)

Thank you very much for your attention to my request. I hope to hear from you shortly.

Sincerely yours. Yours faithfully, (use "faithfully" with "Dear Sirs" and use "sincerely" with a named recipient)

Diego.

In my corrections above, words in blue are suggested as better alternatives, although your text is acceptable without the suggestion. Words in green are explanations.