I checked books 2 and 3. Book 2 is the odd one where the different characters get different sections of the book. That is to say that the first 120ish pages are about Lando and whomever is with him. Luke is in section 2, but it starts with him already in the thick of things. Book 3 starts with Luke on some freighter on his way to somewhere. (Amazing, my attenion to detail!) So I think I've ruled out Black Fleet Crisis. I also cracked Crystal Star, which starts with the Solo kids being kidnapped, so I thouhgt it might be that one. But Luke magically appears on the MF for his first appearance in the book. So, no dice.