Most Helpful Guy
Given that he walked out when you were 3 months along and he has a girlfriend at present I doubt that he will want anything to do with his child. Still he'll have to sign off on his parental rights. If he's asked to pay child support (by the State) he may give you grief and want visitation.
Check with a family law attorney. It's not too soon to see one.
Most Helpful Girl
Legally, unless you two were married at the time you got pregnant, him not being in a relationship throughout the pregnancy is not technically considered abandonment (although this may vary based on where you reside). Request a paternity test right away--even if you are certain he is the father. You can sometimes delay the visits until after paternity has been established. The downside to this is that not all judges look favorably on that stalling technique, because that's really all it is. You can also request supervised visits, although the judge will probably only grant this if you can prove that he he may be a flight risk or a danger to your child. What it all boils down to is that it is as much his child as it is yours.