Are there any Summoners out there that can point me to some info on Summoners?

I've had it at 50 for awhile now but haven't really played it. Not really sure what to do or how to play them. I just did an ST run and I felt like I went full retard.

Any tips would be appreciated as well. I just need something other than Warrior to play 24/7 and I always liked the concept of DoT's.

Thanks in advanced!