There are a few alternatives to BetBlocker so I'll list them here.
In listing them by no means would I say the alternatives are better other than to help players know what softwares exist for helping players to block online gambling.
- Net Nanny
Gamban and Betfilter are probably the best known apps but both operate on subscription models where players have to pay to use the service.
Net Nanny is one that has been around for the longest of ages and is meant to block adult related sites.
Overall what is great about Bet Blocker is that it is free and no registration is required. Perhaps the biggest complaint of the site is that it works so well, if you wanted to gamble again, you'll struggle to remove it from your computer.