I Highly Recommend Soteriology 101
If you want to know what Calvinism is and what's wrong with it, I highly recommend this blog - Soteriology 101 - written by a former 5-point Calvinist who is now speaking out against Calvinism.
And I particularly recommend reading the comments section of each post if you really want to see how Calvinists think (and if you want to read some horrible quotes from Calvinist authors and theologians).
Dr. Flowers allows Calvinists, non-Calvinists, and anti-Calvinist to add comments to the comment section. And these people are very educated and thoughtful. All of them. Calvinists, non-Calvinists, and anti-Calvinists alike. So you get a really interesting, thoughtful, complex, eye-opening look at Calvinism. And at Calvinist
When you read the comments by the Calvinist commenters (you can clearly identify them after awhile), you can see how they spin things, reword things, redefine things, ignore certain truths and logic, and take Bible verses out of context. You can see the assumptions they make about God and the verses they take out of context to support their assumptions, which they then build their whole theology on, never caring that it turns God into an illogical, unjust monster. (And you can see how they fiercely defend Calvi-god's right to be that illogical, unjust monster.)
One commentator, FROMOVERHERE, likes to phrase the Calvinist motto this way: "Never waste a chance to take a half-verse out of context!" Love it! So true!
Some recommended posts and comment sections from that blog:
Factors Beyond The Agent's Control? (These comments are definitely worth reading. Especially look for the comment from TSOO starting with "Calvinism declares that God alone is the sovereign determining force in whatever comes to pass in his creation." It's long, but it's very well-written and very worth reading! It's somewhere in the middle of the list of comments.)
Choice Meat & Bad Form (I particularly like the comment by Graceadict starting with "Hi 5Alive, Great to have you here on this site ..." A great summary of Calvinism and its dangers.)