Which is right? "Someone else and me", or "Someone else and I"?

Well, there seems to be quite a bit of confusion about this point. The fact is both are right ... depending on what you want to say.

We are dealing with a shortened form here, so the easiest way to work it out is the long way. Say the whole thing and see how it sounds. "Jane and him are going to the concert" is short for "Jane is going to the concert and him is going to the concert". Does the long way sound right? Hardly! "Jane is going to the concert and he is going to the concert" sounds much more natural, and is right. Therefore, "Jane and I are going to the concert" is correct.  Similarly, "Tom and I both like reading" is correct because "I like reading" is right and "Me like reading" isn't.

Now, how about, "Our father saw my brother and me in the park"? Try it the long way. "My father saw my brother and my father saw me in the park" sounds right and is right. "... my father saw me..." is right. "... my father saw I ..." is not. Also, "The police sent a fine notice to them" is correct.  "The police sent a fine notice to they" sounds wrong and is wrong.

If you want more help with this point look in Arkana or post a question in a comment.