I've stopped using IsoHunt, now. Yesterday or the day before, I went to IsoHunt and something "malicious" tried to happen. I don't recall what it was and it wasn't the first time I've had that problem there lately.
As for others I use.
http://www.eztv.it
http://www.mininova.org
http://thepiratebay.org/
http://www.demonoid.com
(Have to sign up, but don't need invite. Not sure if they're taking people or not, right now.
http://www.torrentz.com/search
(Very helpful at proving multiple trackers. Scans for torrents on many torrent sites including mininova. Note: Of course, you have to understand how to add them and what they are so you even recognize them when they provide them to you. Sorry, having a hard time explaining it quickly.)
http://www.fullcontactzone.tv
(Must have invite. Predominantly a contact sports site, mostly mma and the like. Very good community. Quite often, I dl UFC ppv's in the time it takes to shower. If you are responsible torrent user, ie; you share the way you're supposed to - at least 1:1, I do have invites for this site.)
There are a few other decent ones out there. I find I rarely need them, though. There is another MMA type torrent site I'd love to get an invite to but I cannot recall the name of it offhand.