correction on it expires the first week of may..
according to the employer i can get an extension.. but i will go to the local office anyhow and stop by, someone mentioned that i can get a temporary extension on the green card if you speak to the right IO.
If your GC is still valid, go
immediately (I mean tomorrow morning) to the local social security office and apply for an updated social security card, with no notation on it restricting your employment eligibility. As a GC holder, you are entitled to an unrestricted social security card. If you apply tomorrow, the new social security card will arrive before May 9. Then you'll be able to use your social security card plus your driver's license when filling out the I-9 form.
Regarding "someone mentioned that i can get a temporary extension on the green card if you speak to the right IO" - that is complete and utter nonsense.
There is no such thing as a "temporary extension of a green card" and no IO, the right one or the wrong one, could issue you such a thing.
The only way to extend a GC is to apply for its renewal by submitting an I-90 application. If you submit an I-90 application online, you will get a printable receipt which you can then show instead of a green card to the employer when filing I-9. After that you'll have 90 days in which to produce an actual green card or another document authorizing your employment and show it to the employer - or else the employer will be required to fire you. In 90 days most likely you will have been naturalized and you'll have an actual U.S. passport in hand to show the employer.
Also, with an I-90 application receipt you might be able to get a temporary I-551 stamp in your passport confirming your LPR status - but I am not sure that such a stamp is acceptable for I-9 purposes. Also, under this option you'll still have to pay the I-90 application fee, which is at least $365.
So it is far better and easier if you use the first option - apply for an unrestricted social security card now, while your GC is still valid, and then use that social security card when filling out I-9 (you'll not need the GC in such a case and it will not matter that your GC will have expired by then).