False FB account was created under my name, & tried to add my entire FB network (including co-workers) by saying this was new account. The profile consists of totally false info, & I do not want my co-workers to even think this type of stuff. Drunken photos were uploaded of me, which I think were stolen from when I had a MySpace (years ago)--stupid mistake. After I saw it, I Google'd myself and saw numerous Yahoo Answers posts from a screen-name that's my full name (so it'll come up in Google searches). Again, totally inaccurate information. How can I get to the bottom of who is doing this? I am almost positive I know who, but how can I go about proving it? Does Facebook give IP information? Also, does Yahoo? Something like this can really impact my career, since I am in many business-networking sites, I do not want a Google search to ruin anything for me.

You have to contact Facebook and Yahoo about this. Use the Help screens until you can get to a place to contact them.

Like in cases of major credit-cards frauds that wont't give out any info to you,same thing with isp/ip adresses from frauds. Contact your facebook/myspace people,and let them know about this,and also tell them what is your ISP(internet service provider). Most likely it is somebody that knows you. Contact all your friends and notify that anymail received from that account,to be forwarded with full headers to the proper support email adresses.

Yes, it is almost for sure someone you know, a stranger would have not reason to do all of this. But you will have to notify them of the problems, most likely send them proff of your ID and so on.