Here's a look at good spots for Tintin information online:
The Adventures of Tintin
An official site for the recent movie and for Tintin's comics adventures. Includes information about the strip's history and characters, plus news and a product store.
Tintinologist: The Cult of Tintin
A long-running fansite for Tintin enthusiasts. Includes news, articles and forums.
The Tintin Blog
Another extensive fansite.
The official site of the Brussels museum dedicated to the art of Tintin's creator, Herge.
Herge was known for his use, and fastidious depiction, of real vehicles in the Tintin stories. This site catalogs appearances by different trucks and cars in the Tintin books, comparing Herge's drawing with photographs of the real things.
Tintin in the Congo
Wikipedia's detailed and balanced look at the controversy surrounding this early Tintin release, which contains stereotypical and offense depictions of Africans.