Who are the Actors in Mad Men?

I thought I knew "Pete Campbell" or Vincent Kartheiser from somewhere but I couldn't tell from where... Well he played Connor in Angel (his son). He is way hotter in real life than in the series, but don't get too excited, because he is currently dating Shanna Collins. I really love his character in Mad Men, as well as Christina Hendricks, who plays "Joan Holloway". It seems she also played in one episode of Angel. She played in series such as ER, Kevin Hill and Life, but I don't think I ever saw her before. She is really gorgeous and about to marry her boyfriend Geoffrey Arend, who is also an actor.

January Jones - what an odd name!- who plays Betty Draper is also an incredibly pretty woman. She started as a model and acted in a few movies and series, notably American Wedding. She dated singer Josh Groban for 3 years and Ashton Kutcher, but I don't know if she is dating anyone right now.
Jon Hamm, who plays Don Draper, the main character in the serie, was a high school teacher before acting, and he has been dating the actress Jennifer Westfeldt for the last ten years. He is very good friend with Paul Rudd, aka the new Hugh Grant.
Elisabeth Moss (Peggy Olson) is engaged to Fred Armisen. She played in more than 50 TV series/movies, including The West Wing, Invasion, and Girl Interrupted with Angelina Jolie. I think she looks a bit like Courtney Thorne-Smith from Melrose Place.
Finally, John Slattery (Roger Sterling) is probably the most famous of them all, as he played notably in Will and Grace, Maggie, Judging Amy, Sex and the City, Ed, Jack & Bobby, Desperate Housewives and soon in Iron Man 2. He is married to actress Talia Balsam.