diference between say tell - Books

CLERK: Hi, can I help you?
CUSTOMER: Yes. I'm looking for something to expand my vocabulary. I bought a few books last year, but they're not very effective. Do you have any suggestions?
CLERK: Well, we have some books on tape. You can listen to them and read along. I've heard great things about this series. How about these?
CUSTOMER: Yes, that might work. Then I could listen on my way to work.
CLERK: And we have English movies on the third floor. Maybe that could help your vocabulary.
CUSTOMER: Yes, but I always end up turning the subtitles on. Anyway, thanks for the suggestion. I'll head up there later.
CLERK: You know, my son is studying English at school now, and they use a website to study.
CUSTOMER: Really? Do you remember the address?
CLERK: What did he tell me? I think it's Englishtown.com. He says it's great.