I just finished my first season today. i did it on easy mode, so I became champion with a great lead.
My offers were from:
-Williams (the team I was racing for)
-Team Lotus (not the gold/black car )
-HRT
-Virgin
-Force India
-Torro Rosso
-Sauber
-McLaren (rival team)
I think the offers are still level based, and you won't get to Renault untill you have finished your second season, I think.
I got mine halfway the season, or a little bit later. It was my first offer for the next season.
I also see some comments that you can get more teams to offer you a contract when you tell the press that you aren't really happy with your team, by telling them that the progress of the car isn't going like you want, and every time you get the option, tell them you did it all by yourself, and it wasn't a team-effort.
I really was a ego-driver, if you could see all of my responces.