How much does the average writer make on his/her first novel?

It really depends, as you already know. There isn't actually an average - most writers get a five-figure advance on their first novels, and if they don't sell, then that figure doesn't go up at all.

Don't go into publishing for the money. Most writers will not be best sellers, although with talent and a lot of luck, you just might be successful.

Best of luck!

Very good question! I don't believe there's an "average" persay, and that it probably depends on the genre. I suppose you just have to really enjoy writing and hope to get lucky!

Best of luck!

well it depends what kind of people your book is directed to. if it is directed toward teens and it has a good theme and interesting cover that cathes peoples eyes that i am sure it will sell well.

That depends on how well the book or writing is written. If it's good enough to get at least a million copies sold the I should say around maybe 5,000.