The way an edition was marked changed over the years. Depending on when your book was printed one of these should work.

1. Edition number will be mentioned on the first or second page of book.

2. Look on the last page of the book in the lower right hand corner by the spine. There will be a letter and this letter tells the edition. For example A=1st, Z=26th, AA=27. It can be well hidden under the spine so be careful.

3. On the bottom of one of the first two pages you will see something like A B C D E or a b c de. The first letter to the far left is the edition.

4. Books printed since late 1991 no longer have the letters of the alphabet designating editions, on the title page. Now the books, besides having the copyright date, will also have a printing date in Roman Numerals. If a book from this period does not have a Roman Numeral date it is a probably a first printing and it was left off by mistake. If the letter "A" precedes the Roman Numerals the book is a first edition. If an "R" precedes the Roman Numeral then the book is a (R)evised edition of an earlier Little Golden Book. If there is not a letter preceding then the Roman Numerals are stating when the book was printed.

5. The new books state First Printing 2003 Or other year at the bottom of the copyright date.

As for your statement about your books being worthless. Book with dashes or printed since 1998 that are not first editions can be difficult to sell for there original selling price.