The show started off of the The Tracey Ullman Show on April 19, 1987. It didn't appear as a series until April 1989 when it first appeared on its Sunday night at 8:00 Eastern (7:00 Centeral) time slot. The first three seasons were animated by Klasky-Csupo, an animator for The Tracey Ullman Show. That is why they appear to be different compared to episodes since.
If you do a search on Yahoo! over 720 web sites dedicated to The Simpsons come up. A Simpsons database offers a behind the scenes look at the longest running cartoon in history. Many other quality sites are available at the Simpsons directory.
Now you can catch Homer, Marge, Bart, Lisa, and Maggie in their tenth season on Sundays at 8:00 Eastern (7:00 Central) on Fox.